Slashdot Mirror
One Hundred Years of E=MC2
Eric Ward writes "To mark the one hundredth anniversary of Einstein's
famous equation, E=mc2, NOVA has gone live this month with a Web site that features exclusive content and podcasts from ten of the worlds top physicists. This once-in-a-lifetime gathering of top scientists such as S. James Gates, Jr., Brian Greene, Neil deGrasse Tyson and Nobel Laureate Sheldon Glashow simplify what the equation means to our world today and the effect it has had on their careers. NOVA online also details how Einstein grappled with the implications of his revolutionary theory of relativity and came to a startling conclusion: that mass and energy are one,
related by the formula E=mc2.
Viewers will also find lesson plans through the
award-winning NOVA Teacher's Guide and a special
library resource kit."
Its E=MC^2/(1-(V^2/C^2))
There once was a fencer named frisk,
whose movement exceedingly brisk
so quick was his action
the Fitzgerald Contraction
reduced his rapier to a disc
+5, Truth
In response to this momentous occasion...I can only quote the great MC Hawking. :)
"I explode like a bomb. No-one is spared. My power is my mass times the speed of light squared."
#!/usr/bin/perl my $e = (mc * 2); print "$e";
*E=MC^2
This sig is o Unfunny o Funny
Site already slow: Coral cache.
--
Dreamhost superb hosting.
Kunowalls!!! Random sexy wallpapers.
Hosting 20G hd, 1Tb bw! ssh $7.95
Einstein's work showed that Newton's equations were a good approximation for low velocities, but not for velocities approaching c. What if Einstein's work is an approximation, too. Perhaps we will discover that the E deviates from mc^2 when temperatures are very high or very low or m is very large or magnetic fields are especially strong.
Newton's 3 laws survived 239 years, I wonder how long Einstein's will last?
Two wrongs don't make a right, but three lefts do.
Richard Stallman created that, not Einstein! And the current release is 21.4, not 2!
... I really have a strange feeling about their web server :(
If you don't fail at least 90 percent of the time, you're not aiming high enough. (Alan Kay)
But m = \gamma m_0, where \gamma = 1/sqrt(1 - \beta^2), and, of course \beta = v/c.
I.e., E = mc^2 = m_0 c^2 / sqrt(1 - (v^2/c^2))
Oh, m_0 is rest mass, in case you didn't know that, and m is the relativistic mass.
Ben Hocking
Need a professional organizer?
I don't know if I fully believe that energy equals mass. The only way that makes sense if something like SuperString theory is true, that we have more than the 4 dimensions (X, Y, Z, and time). To take mass, and BANG, the mass is gone and there is enegery, does not ring true to me. Something more happened than we do not understand. It is like the uncertanty principle. The electron is still there. Or is it? If it is not there, where is it? How many examples are there of the opposite happening. Taking just energy, with no starting mass, and making mass?
What I think is more usefull from E=MC2 is the idea of relativity. It is true, not just for science, but for almost every field of study.
Rosco: "If brains were gunpowder, Enos couldn't blow his nose."
By Peter Norvig.
Don't miss the rest of his site while you're there.
To a Lisp hacker, XML is S-expressions in drag.
I took physics in college and all I got out of it was this cool E=MC2 shirt. :P
Sadly, this comes just days after the anniversaries of the Hiroshima and Nagasaki bombings.
"If Einstein was so smart how come people only call you 'Einstein' when you do something really stupid?" - Brian Regan
So what was E equal to in 1904?
++ Say to Elrond "Hello.".
Elrond says "No.". Elrond gives you some lunch.
It's because you're doing E=MC2, not E=MC^2. Redo your calculations and you'll see everything makes sense now. ;)
:)
Now seriously, I don't get it either.
(Another thing I don't get: why isn't <super> allowed HTML?)
The filesystem is the package manager
Ok everyone, let me proclaim my utter ignorance. I have been trying to understand E=MC^2 for years, and I don't get.
Honestly, I don't even understand many of the basics.
Sure-- it's the formula for "Energy to matter" or something. But why does this matter? How does this relate to Einstein's theories about gravity wells, speed of light, etc.
And I understand the legacy-- E=MC^2 changed how the world was viewed by theoretical physicists. It's different from the Newtonian models of the Universe. I just don't understand why.
Are there any good, visual examples of these ideas?
I'm listening to these Physicists. But again, most of these people are talking about the legacy of the equasion-- they talk about how the equasion impacted society. (Although Janet Conrad has a good brief description of why it matters)
94% of Repubs and 21% of Dems voted to renew the Patriot Act
einstein was awarded the nobel prize for his brownian paper. relativity, published the same year, was all but ignored.
source:t ml
http://www.bun.kyoto-u.ac.jp/~suchii/einsteinBM.h
2 1337 4 u!
I would use floats. And make sure you note the difference between velocity (speed and direction) as opposed to just speed. And it's not just any speed, it's the speed of light in a vacuum. So, this is better:
float getenergy(float mass, float velocity) { }Or:
float getenergy(float mass, float velocity) { }if you don't like using "c" for some reason.
Ben Hocking
Need a professional organizer?
Even if it was plagiarism, the mere article itself made a much greater effect on the scientific community than did the other previous researchers. Sometimes it's not who thought of it but who pushed their point or got lucky who gets famous - that's just a fact of scientific research.
Hm. I call bullshit. The same site appears to also support UFOs and some sort of secret Nazi base in Antartica?
Seems like a scientist's National Enquirer.
"For years, I struggled with reality... but I'm happy to say I finally won out over it." -- Elwood P. Dowd
If you have it that the values are irrellevant and only the geometery matters, then for E to be conserved and still change c...
...which only means that as the speed of light changes, mass must change where it does so that E does not change and violate conservation. And if t is related to c then quite possibly as c approaches infinity m drops towards 0 and the distance between any two points drops towards zero and the speed of time climbs towards infinity and at c=infinity everything happens at once and all distances are zero.
E=(m/(n^2))*((n^2)*(c^2))
where n is the factor by which the speed of light changes.
Conversely if c drops toward zero then mass heads for infinity and when c=0 then mass is infinite, nothing happens, and all distances are infinite.
It looks like reverse time dilation and one wonders if you can warp space to create a faster local c, can you accellarate normally at such a rate as to counter it and have dilation=0? It doesn't look so much like Star Trek's integral warp speeds as there being a curve on which normal dilation can match warp dilation. Would be interesting to have a high-speed zero dilation trip to the next system and back to check it out with chronometers.
Just thinking out loud is all...
If my grammar and spelling are off, I am [distracted/tired/careless] (take your pick)
What if Einstein's work is an approximation, too. ..
That's the beauty of science... Science is INQUIRY... it is not static.
Until someone does prove it was an approximation, we'll use it. Once that occurs, we will use the new figure until someone else is able to make it more accurate.
Ignorance is not a crime; neither should it be a way of life
Congress control $ = inmates run the asylum
I don't know the details, but if Newton and Leibinitz can come up with calculus independently of each other (b/c it is true) do not assume Einstein stole the formula without proof.
Except for ending slavery, the Nazis, communism, & securing American independence, war has never solved anything.
This word "anonymous." I don't think it means what you think it means.
Nexus is a magazine devoted to printing what nobody else will publish despite glaring scientific inaccuracies and holes in logic. that is part why they publish what they do.
years ago they were pushing naltrexone for blocking the effects of drugs like opioids and many stories talked of its completely safe use and ability to fix drug users in just days or weeks and prevent any relapses, and was an immune system miracle drug that beat HIV and AIDS.
then after naltrexone was approved nexus printed many articles afterwards talking about the mind control use of naltrexone which was being sneaked in the back door by making drug users use it first because that wouldn't be rejected by society even though there is claimed all evidence to it being unsafe.. claims now are the whole population will be on naltrexone and under mind control within decades.
the position switch might sound like nexus is dual personality but really it just cmoes about because they feel the same information wants to be free as many other people but will work towards that by publishing information nobody else will publish.
whether that information is bollocks matters not it will be published anyway.
when we sqaure c, we aren't getting another speed, we are just getting a number that is fastest speed ever, multiplied by itself.
Actually it does. Kind of. If I remember my Advanced Cosmology class. One of our first assignments was to figure out how much energy you would get by bringing in 1 kilogram of antimatter in to contact with its corresponding regular matter. Providing all the matter and antimatter are converted.
While you use e=mc2, The part that a lot of people forgot was that you get twice the energy because while you get the energy of the conversion of antimatter you also get the energy from the conversion of normal mater.
500 dollar reward for tip(s) leading to the arrest of the person(s) who stole my sig.
E = mc^2 is Not Einstein's Discovery
...
Robert A. Herrmann
1. Introduction
It appears that some scientists have not received the proper credit for significant discoveries for which they have priority. However, without specific and irrefutable information, it is not possible to give convincing reasons why these individuals have been denied recognition and why others have been given credit for their scientific discoveries. In 1996, I was asked whether certain aspects of General Relativity were originally formulated by Einstein or Hilbert. (Hilbert presented the gravitational equation(s) prior to Einstein.) The questioner said that he knew very little about Einstein's achievements except for such things as "E= mc^2." I answered his question relative to the Hilbert verses Einstein controversy but I neglected to discuss the more easily explained E = mc^2. What follows in this short article shows exactly who developed the idea that "radiation" can be characterized as having an apparent mass and that it was not Einstein in his 1905 paper. Except for the last remarks on Olinto De Pretto, this article is concerned mostly with "radiation" and its relation to E = mc^2.
read more...
Michael.
Linux : Mac
You don't usually hear of a genius physicist named "Chuck Miller"...
Rory Carroll in Rome
Thursday November 11, 1999
Guardian
The mathematical equation that ushered in the atomic age was discovered by an unknown Italian dilettante two years before Albert Einstein used it in developing the theory of relativity, it was claimed yesterday.Olinto De Pretto, an industrialist from Vicenza, published the equation E=mc2 in a scientific magazine, Atte, in 1903, said Umberto Bartocci, a mathematical historian.
Einstein allegedly used De Pretto's insight in a major paper published in 1905, but De Pretto was never acclaimed, said Professor Bartocci of the University of Perugia.
De Pretto had stumbled on the equation, but not the theory of relativity, while speculating about ether in the life of the universe, said Prof Bartocci. It was republished in 1904 by Veneto's Royal Science Institute, but the equation's significance was not understood.
A Swiss Italian named Michele Besso alerted Einstein to the research and in 1905 Einstein published his own work, said Prof Bartocci. It took years for his breakthrough to be grasped. When the penny finally dropped, De Pretto's contribution was overlooked while Einstein went on to become the century's most famous scientist. De Pretto died in 1921.
"De Pretto did not discover relativity but there is no doubt that he was the first to use the equation. That is hugely significant. I also believe, though it's impossible to prove, that Einstein used De Pretto's research," said Prof Bartocci, who has written a book on the subject....
Seastead this.
But I have a few nagging question about this famous equation. People just tend to explain c^2 by saying something like "a little matter represents a lot of energy, and c is a big number and so c squared is even bigger". Well, that certainly is true if c is measured in meters per second or any other common unit. But it's all about the units. If c is expressed in light-seconds/second rather than meters per second, or worse yet light-years/second then the "logic" of that argument is exposed as just hype. So the real issue comes down not to the equation e=mc^2 itself, but the selection of the units that e, m and c are expressed in. Use a different unit and, as I try to show above, the whole thing breaks down.
Al himself made a pretty famous point of saying that c was a constant. So c^2 is also a constant. So the equation boils down to expressing an important relation between e and m. But it all depends on the units of measure. So here's the question:
Is there some science behind the selection of the units involved that allows this equation to be so simple, or are we to believe that some serendipitous magic just allows this to be an exact equation and the units somehow just happen to match up? After all, I certainly don't know of any reason why a meter is any more of a valid unit to do this calculation with than a furlong, or a foot, or a parsec. And I am under the impression that the units of both mass and energy were determined before the equation, not as a result of it. So should I believe that this equation is just a serendipitous chance match up of units, that Einstein made some sort of deal with God, or that the equation just might be a bit over simplified?
If a meter were and inch shorter or an inch larger, there would still be an equation that could show the relation between e and m, but a conversion number would have to be added to the equation to make up for the slight difference in the size of the meter. How is it that this equation works out with the current rather arbitrary length of a meter to such whole numbers?
I'm an American. I love this country and the freedoms that we used to have.
As my mass has gone up, my energy has gone down. What more proof do you need?
Exactly. Thats one of the problems scientists face with fusion power for example. Fusion as a means of an energy source was proposed back in the fifties. When old Albert was barely in the grave infact. Since then they've made modest progress, as many on /. have no doubt heard, a fusion reactor named ITER was approved for construction in France.
Thing is, though ITER is widely expected to be relatively (ha-ha) more efficient than past fusion reactors, it'll still be experimental. By that I mean it'll still be inefficient in terms of energy produced from materials used. We have a heck of a long time to go before we can even make an energy "profit" from materials put in. The most optimistic scientists predict 2040 as the crossover point. But then, only time will tell.
A second problem is that some environmentalists believe all E=MC^2 ever acheived was "The Bomb" and as such try to obstruct progress through protesting etc. It is true that fusion can pollute, but to a much lesser degree than nuclear fission. Still, perhaps in fifty, a hundred, two hundred years time when fusion becomes widely used they'll be chaining themselves to trees and whatnot.
We'll no doubt find that development in fusion and other methods of power will speed rapidly once oil/natural gas become scarce enough. And with that, hopefully, journeys to Mars, to the Centuari system, and beyond on fusion powered craft.
nothing is faster than the speed of light
That's not what special relativity says. Special relativity says nothing can travel AT the speed of light. It says nothing about FASTER.
Mod down people who tell people how to mod in their sigs
> how can we square c?
.__
|
|__
That ought to do it. Pesky formatting seems to insist on the period, but it looks *far* more squared to my eyes than "c".
How many examples are there of the opposite happening. Taking just energy, with no starting mass, and making mass?
Here's the link you need to CD Anderson's 1932 experiment using gamma rays
Ignorance is not a crime; neither should it be a way of life
Congress control $ = inmates run the asylum
Another interesting fact, derived from empirical analysis : in a Windows field, light speed is negative.This explain the interesting "expanding copy time" (aka "30 seconds left... 4 centuries left...") experienced by most Windows users.Another explaination would be a schrödinger-like effect induced by closed source.
I'm jack's useless sig
If you write Newton's laws with the covariant 4-momentum, don't they still hold (pdot = Force)?
Helium balloons want to be free.
...how can we square c ???
Get c to marry Bush or Blair or some other 'trendy person'.
100th anniversary? Yeah, but it's all relative
Why not? Ben ignored / abondoned all of his family except for his son, who worked with him on most of his major findings.. including political ones. If you didn't have a whole lot of social bullsh*t, except for womanizing, I bet you'd get a lot done too. ESPECIALLY if the only focus you had was a helpful son and women to impress. Studies have shown that scientific men just "happen" to do their best in their early to mid twenties just as they are meeting / courting their first wives.
so tell me again why he couldn't do this if, say, an egytian, Imhotep, who designed the first pyramid, the Step Pyramid of Saqqara, is considered by historians to be the first genius, a brilliant physician and surgeon, as well as, a healer could do it 5 thousand years ago?
** "It's not my job to stand between the people talking to me, and the ones listening to me." -- Pego the Jerk
Please. Einstein was awarded the Nobel Prize for his work on the photoelectric effect. He did publish a fantastic work on Brownian motion as well. If you had RYFSM (read your f**king source material) you would also know that, since it says so in the first paragraph.
/. and I should be happy with that.
I guess its just
Ummm, no. Einstein's NP was for his paper on the photoelectric effect. Read your source again.
"Lawyers are for sucks."
- Doug McKenzie
It wasn't so much that relativity was ignored, as much as it was that the Nobel committee didn't want to award the prize for a theory for which there was not much proof yet. The fact that Einstein was given the Nobel prize for his other work was more of a nod to him than anything else.
With a calculator?
Doesn't it make you feel good to know that our freedoms are protected by politicans, lawyers and journalists.
Thank you, thank you, I'll be here all week.
c squared is not a speed. If c is in m/s then c squared will be in m^2/s^2. Multiplying by a mass in kilograms gives us an energy unit of kilogram square meters per second per second.
Note that a newton, the unit of force, is a kilogram-meter per second per second. The Joule, the unit of energy, is a newton-meter, or a kilogram square meter per second per second.
I have seen the future, and it is inconvenient.
Plenty of things travel at the speed of light. Just no things with mass != 0.
how can we square c
god just takes the log and doubles it.
try { do() || do_not(); } catch (JediException err) { yoda(err); }
I hate to be a killjoy, but I always thought a brownian motion was what happened in your pants after you've had too much to drink and had a sudden scare...
PocketGamer.org - For the gamer on the go!
Speed squared is no longer speed. Just like length squared is no longer length. To get technical: speed (in meters per second) squared = (meters squared) per (seconds squared). Or, if you prefer, joules per kilogram (a constant).
#include "humorous_pop_culture_reference.h"
By 1921, there was ample evidence of the relevance of relativity, special and general. The real reason for not awarding the Nobel for relativity was because of what was dur to Poincaré. See my reply as an AC to the post you reply to before I found my pw again.
(geeks+intelectuals)-(1st posters+flamebaiters)*(low bandwidth)= "/.effect" ...somebody better be able to do way better than this BTW....
Don't ya hate it when the correct spelling of your favorite screen name is taken?
http://www.pbs.org/wgbh/nova/rss/
they said podcast first
To begin: Wolfgang Pauli postulated the neutrino, not Einstein.
Next: Whatever one concludes about the validity of Eddington's solar eclipse experiment, the predictions of General Relativity have been tested and proved out in hundreds, if not thousands, of repeatable and rigorous experiments since then.
And Next:
This quote falls somewhere between the irrelevant and a non-sequitur. Thanks for sharing man--but what does it mean? No physicist takes cold fusion seriously, and autodynamics is a competing theory to General Relativity, for which Richard Moody, Jr. is clearly a shill.
At the end of the day, it doesn't matter whom it was that provided the first, or the first accurate, derivation of e=mc^2. It could have been Einstein, Poincare', or William goddamn Shakespeare, for all I care. What matters is that both Special and General Relativity have withstood an awful lot of testing over the last century, and stood up well under that onslaught.
The autodynamics camp also seems to believe that Special Relativity is used in radioactive decay calculations, and I could have sworn that Quantum/Statistical Mechanics holds sway there....
I'm the mc squared, at the speed of light
My rhythm is loose, but my rhymes are tight
From the heart of the Sun, into your eye
Call me irrational, I'm easy - as pi
(C) 1988, 2005 mc squared
--
make install -not war
Is Brian Greene a top scientist, or just a famous one?
Errr, n^2 cancels out on the right hand side, no?
-mkb
Einstein was not awarded the Nobel for special relativity because much of it was in fact unveiled by the great mathematician Henri Poincaré. Poincaré found the key point, i.e., everything stems from defining time as being obtained by synchronizing clocks with electromagnetic signals.
Not really. Poincare did do a lot of the interesting math, following on from Lotentz, that provides a lot of the mathematical foundations for relativity, but what he didn't do was redefine time. Poincare still viewed the different time in the calculations as a sort of "local time" which was in a sense merely a mathematical fiction required to make the calculation go through. Poincare still believed in the ether, and thus an absolute referene frame and an absolute time. It was Einstein who, with his observations about the very nature of time being relative, did away with a ficntional "local time" and an absolute reference frame. In Einstein's view there was no true reference frame and all time was "local time" - local to the observer. The effects on time were thus not a mathematical fiction, but a physical reality. It was this observation and new conception of time that Einstein is highly regarded.
That does not, of course, in any way diminish Poincare's work - and he did a great deal of work besides just that relating to relativity (he is the father of algebraic topology for instance). Certainly Poincare deserves a little more recognition for his great achievments than he gets outside of the mathematics community. Misrepresenting Einstein's achievements is not the way to give Poincare his due credit however.
(As a side note, more recognition should probably also be given to David Hilbert, who did a lot of the pure maths required to lay the foundations of General Relativity).
Jedidiah.
Craft Beer Programming T-shirts
"When you are a student, it's called plagiarism; when you are a professor, it's called scholarship."
But for all I know he ripped that quote off from someone else . . .
http://en.wikipedia.org/wiki/Oliver_Heaviside
Oliver Heaviside is one of the forgotten men of science, much like Philo T. Farnsworth (inventor of the electronic television) is one of the forgotten men of engineering.
As well as casting Maxwell's equations in their modern (vector) form, he contributed to work in relativity, and if memory serves first wrote down E=mc^2 in 1892. David Bohm's book on special relativity covers this in considerable detail.
This is not to diminish the contribution of Einstein, who worked mostly independently of previously known results, but to make it clear that there were others who set the stage for Einstein's great performance.
The fundamental contribution of Einstein was his ability to show that results that had previously been derived by people like Heaviside and Lorentz with great difficulty from an electro-mechanical dynamical model of the electron could be generalized and proven very simply as a result of a purely kinematic invariance.
Blasphemy is a human right. Blasphemophobia kills.
Nexus is a magazine devoted to printing what nobody else will publish despite glaring scientific inaccuracies and holes in logic. that is part why they publish what they do.
The parent post is not a troll. Check out these SHOCKING and AMAZING stories from the current issue!
"BRITAIN'S SECRET WAR IN ANTARCTICA--Part 1
By James Roberts. At the end of World War II, Britain sent a covert mission to Antarctica to seek out and destroy a subterranean Nazi haven."
"Exactly 50 years after UFOs buzzed Capitol Hill in Washington, DC, in July 1952, gravity-defying objects penetrated restricted airspace and even landed on the Capitol Building."
And from previous, obviously peer-reviewed scientifically sound issues:
"TUNGUSKA & THE ANCIENT MYSTERY INSTALLATION IN SIBERIA"
"THE HENOCH PROPHECIES"
"OUT-OF-BODY EXPERIENCE & SELF-RESEARCH"
"UFOs & THE DRAGON SNAKE"
Next time put down your healing crystals and anti-Reptoid force shields before moderating please.
"...always new atoms but always doing the same dance, remembering what the dance was yesterday." -Richard Feynman
FWIW, E=mc^2 was a pretty good book on the subject and a very enjoyable read.
Have fun: Join D.N.A. (National Dyslexics Association)
If we are getting pedantic...
[PEDANTIC]
For things like photons that have zero rest mass
E = m0*c^2 / sqrt (1-(v/c)^2)
Doesn't work so well... By using the following:
(E^2) = (m0^2)*(c^4) + (p^2)*(c^2)
Now photons (which by definition are moving and have momentum) can have kinetic energy associated with them without having to divide zero by zero (since photons travel the speed of light v/c = 1 and the denominator is zero in your equation).
[/PEDANTIC]
E=mc2 is a "sexed equation". Newton's Principia (a "rape manual"):
p osts
http://www.freerepublic.com/focus/f-news/1076200/
Thanks God I went to college a long time ago.
Give a man a fish and you have fed him for today. Teach a man to fish, and he'll say "WHERE'S MY FISH, YOU IDIOT?"
Among the names given in the summary, there is no doubt that Sheldon Glashow was a top scientist - twenty years ago. As for Brian Greene, Neil deGrasse Tyson and S. James Gates, they are good science popularizers, and competent physicists in all likelihood. However, I think they would be the first ones to pooh-pooh the notion that they are top physicists in a world ranking.
Mod parent up, this one is right. GP is WRONG!
To add to something to the general debate, I once found this
Einstein's conventions and interpretations were sometimes ambivalent and varied a little over the years; however an examination of his papers and books on relativity shows that he almost never used relativistic mass himself.
from this source.
> However, Einstein certainly deserved a Nobel
> for one reason or another and another excuse was chosen.
While I agree that awarding the Brownian motion paper was an excuse, proving the existance of atoms logically at a time when the atomic hypothesis of matter was not settled is definitely not chopped liver.
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
einstein was awarded the nobel prize for his brownian paper. relativity, published the same year, was all but ignored.
All but ignored? I would say that the brownian motion is in full effect at my office.
The paper seems to be basically saying that Special Relativity is a special case of General Relativity, which IIRC is true. But then you see the context in the author's homepage, and, well, yes, he does appear to be a little goofy.
Which all points to the dangers of mixing science with politics and religion. You can piss away a lot of credibility that way, and luckily Einstein never claimed to be an expert at either.
Give a man a fish and you have fed him for today. Teach a man to fish, and he'll say "WHERE'S MY FISH, YOU IDIOT?"
"E=mc^2 is crankin'!"
"We are fortunately not bathed in that level of energy because we would first get sterilized, then it would mess with our DNA, then we would die."
We raise our slide-rules high.
According to many current theories, photons have zero rest mass, but still have momentum (another mysterious conservation book-keeping number like energy except it has the ability to describe the movement of energy from one place to another using massless photons or electromagnetic waves).
When this photon with a certain momentum strikes your solar sail, depending on the precise interaction with the matter in the sail, transfers some of it's momentum to the sail.
Which is why this whole thing makes more sense when you talk about with this type of formula...
E^2 = (m0^c^2)^2 + (p*c)^2
Assuming we aren't converting any "rest mass" to energy in the interaction, conservation of energy implies that we are going to conserve relativistic momentum and we don't get no perpetual motion machine (unless you count motion as drifting in mostly the same direction as the original photon)
If speeding up Mass gets us Energy, does slowing down Energy get us Mass?
For example, if we slowed down photons enough, would they accumulate into something of serious Mass?
DEAD DEAD DEAD DELETE ME
distance themselves from the poor sap proposing such sacrilege
No, you're not the only one. When I talk to "scientists" (I'm not one either), and even hint that Einstein's theory might be wrong, it's as if I've shouted out a stream of profanities at church.
Slowly, but ever so surely, the scientific community is throwing out objectivity and clinging to tradition. In a round about way, scientists are becoming the new priests; just as a man of the cloth devotes years of study to the divine and carries a significantly greater knowledge and understanding of the mystical over the lay person, the scientist too follows a rigorous course of study and understands the physical world in a far more advanced way.
The objective is the same: "The search for the truth". But the key difference is that scientists are supposed to be objective in that search. I'm disappointed when I ask a particularly religious person a tough question, and she uses the "I know it's true because it's in the bible" response. I'm just as disappointed when I ask a scientist an equally tough question and get an "I know it's true because it was published in the journal of XYZ"
From an objective perspective, the scientist can typically be more confident in the validity of something published in a journal of note because it is assumed conclusions were reached using the scientific method and stood up to rigorous peer review. But these days, you will never see anything published that contradicts the core beliefs of the scientific community.
A scientist today who stumbles upon a discovery that, among other things, disproves the theory of relativity, and who can make a compelling case to justify further expenditure of money and resources to bring his hypothesis to fruition, has no chance whatsoever of receiving funding. In fact, if he chose to continue this work and be outspoken about it it's likely he'd lose is position if he worked at a university or think-tank. He would be an outcast and a pariah in the academic world, even though all of his conclusions have been reached through objective reasoning via the scientific method.
This kind of closed mindedness in the academic world is eerily similar to the world some time ago when the Church prohibited any science or reasoning which suggested the fallibility of the Church's core beliefs. It was wrong then, and it's wrong now.
I'm not saying Einstein was wrong. As a laymen myself, I couldn't come close to understanding the nuances of his theory so it would virtually impossible for me to comment on its validity. I'm simply saying that it's folly for the scientific community to not even consider alternatives. (And no, I'm not saying that a religious perspective should be considered; religion has no place in science)
The Internet is generally stupid
Judge by the content, not the credentials.
Shut up, you bozon!
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
That does not, of course, in any way diminish Poincare's work - and he did a great deal of work besides just that relating to relativity (he is the father of algebraic topology for instance).
And more importantly, he almost singlehandedly created the field of dynamical systems.
Doggone it! Did I get snookered by a wonk? Thanks for the follow up. I'll be sulking in the corner.
Michael.
Linux : Mac
I feel sorry for Lise Meitner; never receiving the recognitiopn she deserved. F**king Nazis.
My web domain.
Einstein's NP was for his paper on the photoelectric effect.
The Nobel Prize is not awarded for a single act or document, but for a collection thereof. Books do not win Nobel Prizes, for example. Authors do.
That's somewhat backwards. In math, someone usually calls a result a lemma to indicate it is a preliminary result being used to prove a more important result. What you are describing would usually be called a corollary.
No if anyone "observed" that time was relative it was Michelson-Morley. Einstein postulated this observation as the basis of a formal system which yielded new testable hypotheses.
Seastead this.
You're wrong. MOND is a subject of current research in the scientific community, and that throws Newton out of the window (which takes Einsteinian gravity with it).
You might have met some bad scientists (or they might just have been trying to shut you up... the famous ones apparently get a lot of crackpots writing to them and I imagine that would eat up your patience).
I quit!
Yeah, slashdot won't allow the tag for this posting. But for crying out loud, how about E=mc^2, at least?
Damn. Self-proclaimed "nerds", unite! Or something.
A few years ago the National Library in Canberra had an extremely popular exihbition called "National Treasures" or something like that. It was a collection of many historical and influential works like ancient maps, the original lyrics to "Yesterday" by Paul McCartney, and other incredible things I've forgotten about. Included amongst them was Einstein's original paper on relativity open at the famous equation E=mc^2.
A German friend of mine went and saw it, and when he read that page he laughed because Einstein had written (in German) a long explanation concluded by 'this can be aproximated by the equation E=mc^2'.
We both hoped that all the physicists around the world knew that the equation wasn't acurate :)
Einstein was awarded the Nobel in 1921 for contributions to physics, and especially the photoelectric effect which demonstrated the quantization of photons.
E = hf
where E is energy, h if Planck's constant, and f is frequency. The energy of light is limited to a multiples of a constant (h) and determines the color (frequency) of the light.
Without this, Bohr doesn't develop his electron model and a lot of twentieth century physics doesn't get discovered.
The existence of atoms cannot be proven logically... Thompson, Poincare, Rutherford and others tried, but his deduction had many flaws. that were revealed by John Synge.
l'Homme n'est Rien l'Oeuvre Tout: Gustave Flaubert to George Sand
Slowly, but ever so surely, the scientific community is throwing out objectivity and clinging to tradition.
Me: I have made an astounding discovery! Did you know that your office chair is actually broken? It is wrong to say it will hold your weight.
You: But I have been sitting in this chair every day for the last five years and it has worked fine. Because I know it would support my weight, I even stood up in it the other day to retrieve that dart in the ceiling.
Me: Nonsense. Being able hold your weight is just a theory. I have the proof right here that the theory is wrong. I have spent weeks going over the math. I have a PhD in advanced math. There can't possibly be a mistake! See, it even explains that funny squeaking noise it makes! Obviously, it's correct! Quit clinging to your dogmatic beliefs!
You: You are nuts. It may be a theory that it can hold my weight, but it has been experimentally verified day in and day out for years. That's the experimental reality!
Me: Bah! You are just like the others. Blindly holding on to these traditional beliefs like its some sort of religion. You have lost your objectivity and bow before the priesthood of the scientific establishment.
You: But the experimental data...
Me: Your mind is obviously closed. Revolutionary theories just can't get heard these days. Feh!
dude it was a joke. laugh.
That's a fallacious analogy. If you want to use chairs, this is closer to what I'm talking about:
Me: I've discovered a fantastic new chair that could very well be the most comfortable and ergonomically designed desk chair to date.
You: That's impossible. My Herman Miller Aeron chair is the best designed office chair in existence. Nothing can exceed it.
Me: I don't know. I've tried both and this feels a lot better.
You: (opening desk drawer and pulling out Aeron brochure) Look, it says right here "The most comfortable and ergonomical chair in the world". Does your chair have a brochure that says that?
Me: Well, no... but I really think that...
You: I didn't think so. Stop wasting my time.
The Internet is generally stupid
We are talking about e-mc^2 here. Not the Special theory of Relativity. Not the General theory of Relativity. Not relativity at all. I'm just asking (and still not quite convinced) how it happens that a formula based on joules, kilograms and meters can just happen to work out in nice round numbers. I do understand the relationship between mass and energy; I don't yet accept what links joules, killograms and meters so serendipitously in this simple equation.
I'm an American. I love this country and the freedoms that we used to have.
A scientist today who stumbles upon a discovery that, among other things, disproves the theory of relativity
Baloney. Any scientist who stumbled upon such a discovery would be absolutely guaranteed to win the Nobel Prize and probably get as much funding as the wanted.
I'm simply saying that it's folly for the scientific community to not even consider alternatives
You seem to think that no one has ever tested Einstein's ideas. Well, people have, and they've passed. So far. If someone comes up with another theory, it must explain everything as well as Einstein did, better in fact, and it must be testable.
You can go onto Usenet and find a dozen crackpots who claim to have overturned Relativity. They all tend to fail because the crackpot hasn't understood some basic principle, or don't know that there's already been experiments which rule out their ideas.
We're celebrating Einstein's work on relativity, brownian motion, and the photoelectric effect.
World Year of Physics 2005
Well, it's been over 20 years since I read my source materials concerning Einsteins theories, but wasn't the e=mc^2 from photoelectric effect, not either of the reletivity theories?
I guess I'll have to dig some old books out and reread some stuff.
...the greatest physics jokes collection. Lots of other science jokes there as well.
obviously this is not "the end" of physics- quantum mechanics and general relativity need to combined in a consistent theory. perhaps strings, m-theory, etc will be it.
to challenge relativity (special or general) or quantum mechanics is simply very very hard. all experimental data that has been done and confirmed agree w/ the theory. more importantly, there is no data that directly contradicts the theories. therefore, to propose a new theory, it not only has to predict the same as the old theories (so it agrees w/ experimental facts), but it must also predict something in disagreement w/ the old theories for it to be tested.
to "mention challenging theories" is fine, but show me what's different. otherwise, yeah, you're a flake. show me and let's do the experiment- we'll be set for life!
yes, i'm a physicist. yes, the b.s. meter goes off when people say current theories are wrong but don't have any way to test that hypothesis.
Other sites have similar info on Olinto de Pretto.
answers.com
Tag lost or not installed.
When I talk to "scientists" (I'm not one either), and even hint that Einstein's theory might be wrong, it's as if I've shouted out a stream of profanities at church.
it's not because they thought you shouted profanities in church, it's because you're showing remarkable lack of understanding of the scientific method and how science is done. if you want to be taken serious, propose your model, show how it explains an observable fact that current theories don't.
being a physicist, i can't believe your post. do you really believe what you say? more importantly, does anyone else? not only is your 'discourse' lacking in supporting evidence, but it's clear you don't know how science is conducted.
one does not simply accept something that's published because it's published. yes, it makes a difference what journal, but that is what references are for- a paper which doesn't give enough details to be reproduced is useless.
have you heard of tenure? it's very hard to get fired if a professor has tenure regardless if he puts forth crackpot theories. to suggest scientists are priests and are afraid of dogma is unfounded and completely false. it's hard to disprove a standard theory simply because the standard theories are the cumulative sum of all of mankind understanding.
physics always consider alternatives. how else do you advance understanding? it's the willowing of all these alternatives that have given us relativity, quantum mechanics, statistical mechanics, electromagnetism, etc.
really, the natural sciences are not a religion. it has to do something, everytime. "objectivity" not "clinging to tradition" is what insures your computer works, electricity is on, gets a probe to Mars, etc.
i do hope you are simply a troll...
n/t
Ben Hocking
Need a professional organizer?
Actually it is more correct to write it as:
E^2 = p^2c^2 + m^2c^4
"relativistic mass" is a very bad concept to learn (something which even Einstein pointed out). A far better way to think about it is that our classical definition of momentum is just a low energy approximation of true momentum. The mass of a particle, just like its charge, is something that does not change.
Actually this is not consistent with special relativity. Special relativity allows me to convert mass into energy so suppose I start with a neutral pion. This can be travelling at a constant velocity when it decays into two photons. Suddenly I have now have no mass and my speed is that of light...and no external forces acted. Ooops!
Newton's Second Law: that the change in motion is proportional its change in momentum
First that is NOT Newton's second law since Newton actually defined momentum as "motion" and the above is just that definition - no physics involved. The correct law is:
The rate of change of momentum of a body is proportional to the external force applied.
This is only correct if you use the 4-vector definitions for force and momentum and not Newton's. Thus, the law as Newton wrote it is wrong.
Newton's Third law, Every reaction is met by an equal and opposite reaction is simply conservation of energy and is not violated in any classical theory, of which relativity both General and Special are.
Ok lets fix this one...first a minor point: relativity is NOT classical physics. Now consider trying to stop a relativistic cricket ball (or baseball for you Canadians out there). The distance moved by the ball while you stop it will vary depending on whether you look at it from the balls point of view or the cricket pitch's point of view. Since, as you point out energy is force times distance the ball and the catcher will both observe different forces. Thus NIII is not correct either...unless you use 4-vector definitions for force.
What Newton was wrong about (and it's not really fair to call him wrong since ......)....and the nature of light as a particle.
Oh boy this is so utterly wrong it is even funny! One of Newton's most amazing ideas that turned out to be CORRECT was the particle nature of light, although the lacked the means to prove it. What is so ironic about your statement is that Einstein was the one who showed that light behaved as a particle in the same year as his relativity paper. Thus the one time you would be correct in saying that Einstein showed Newton to be correct you instead say he is wrong!
As for calling Newton wrong I think you have got confused between cause and effect. Newton was wrong BECAUSE he lacked the means to discover relativity. This does not make him any less wrong. His achievements were amazing given his resources and the previous state of physics and no amount of time will alter that...but he is still wrong! Even at everyday energies Newton's laws are only approximatations and are not correct. However they are such good approximations and so much simpler to understand that we still teach them to school kids. Newton was an amazing genius, arguably even more so that Einstein: he also made huge contributions to maths [~invented calculus] and anti-counterfeiting measures [as master of the royal mint]. His contributions to physics were incredible, but still in the end his laws were proven wrong just, as I am sure, we will find a lot of our current understanding will not quite be correct in a hundred years from now.
I have not read every last comment, but it seems nobody understands, including the people who mentioned that others wrote and published "E=mc^2" up to ten years before Einstein, what its true significance is, or why Einstein gets credit.
It is somewhat straightforward to derive E=mc^2 from Maxwell's equations, just as Fitzgerald derived the correct equations for the contraction of a moving object in its direction of motion. But the key, the big thing, that Einstein did was not just derive by rote an equation, but assign consistent physical interpetations to those equations and make some pretty bold predictions. He put the thing together.
For instance, many people keep saying "E=mc^2" means that matter and energy can be "converted" from one to another. THat is actually incorrect - the MEANING of the equation is that the TOTAL ENERGY CONTENT of a system can be derived by noting its resistance to changes in motion as a result of applied force; i.e. its mass. In other words, the MASS of an object, as measured objectively, describes the TOTAL ENERGY CONTENT of that object as per E=mc^2. Or, put more simply, a boiling pot of water has slightly more mass than the exact same pot at room temperature. E=mc^2 can be shown to be a consequence of Maxwell's laws; Einstein's boldness was in asserting that ALL forms of energy, not just electromagnetic, are imbued with mass (a resistance to changes in motion) in proportion to the amount of energy within. His general theory of relativity tied this idea of inertial mass with gravitaional mass, by again boldly asserting that they are the same thing; this is by no means obvious (Eotovs experiments back it up to 10 significant figures, tho). And neither gives a clue about how to extract nuclear energy; all it says is that objects have an internal energy as evidenced by the fact they have mass; accessing that energy is a completely different matter.
Concisely put, the relationship is the same nomatter what units you use. For example, "E" in this case is energy, defined in Joules, where a Joule is (approximately for comparison) the amount of force required to lift 1 kilogram of mass up by 10 centimeters
In Imperial measurements, the relation would be identical, except for semantic differences. The closets unit of measurement in the Imperial system to the Joule the foot-pound, which is the amount of force required to lift 1 pound of material up by 1 foot (a Joule is equal to 0.737 foot-pounds).
If you expressed E=mc^2 in terms of Imperial terms, it would be the same except that E would be in foot-pounds, m would be in pounds, and C would be in feet per second. So the numbers would change, but not the relationship.
---- I'll take you in a Hunt deathmatch any day.
That's a fallacious analogy.
Actually, no its not. You just missed the point.
Which is that the Einstein's theory has been subjected to test after test since it came out and every credible experiment has supported the theory. Carl Sagan said (paraphrasing), "Extraordinary claims require extraordinary evidence." Relativity has passed this test. In spades. That's why its so well regarded, not some mystical belief in the "scientific dogma" or some misplaced reverence for Einstein.
People are coming up with theories all the time that say they have "proved Einstein was wrong". Trouble is, 99% of these are put forth by crackpots, people with agendas, or people who otherwise have no clue what they are talking about. The other 1% are serious theories by credible people who have followed normal scientific channels. Nothing wrong with that. So far, however, all of these have failed the acid test: real world observed data has not matched the predicted outcomes. End of theory.
Thats what its all about. So, you'll have to forgive scientists if they are tired of hearing all these "revolutionary" theories they can tell right away are bogus, and then being accused of being closed minded because they refuse to waste their time checking out obviously stupid theories.
I admit it, I am crazy and my mind entertains me.
I think I could be friends with anyone who made this statement...
Now... are you and your mind two different things and if you are not your mind, who/what are you?
While I do have a BS in Physics/Math, I lost interest in these when I became more interested in HOW it is that I solved physics problems. How do I do it? To learn about this process I study Buddhist meditation.
But, to those who still want to study physical reality, please, please, please, read the following and tell me what you think. I did read this and I think it makes Einstein almost look like an amature, but I would rather spend my energy into studying the nature of thought than alternate views on reality.
Autodynamics
How can the icon of modern Physics be wrong? Well believe it or not, tens of thousands of physicists, engineers, scientists, and students around the world believe very strongly that Einstein is not correct. This does not Diminish Einstein in any way. His equation E=mc^2 and his Nobel Prize work on the Photo-Electric effect are still brilliant. It is simply time to move onto a greater truth.
Autodynamics
Ok, I'm double-posting this, but I really want to know what you smart physics Slashdotters think. I even got this turned down down as a "Ask Slashdot" question a couple of times!
The Nobel Prize is not awarded for a single act or document, but for a collection thereof. Books do not win Nobel Prizes, for example. Authors do.
Not really. In the Nobel prize for physics is almost always given for something specific that a person did. In Einstein's case it was awarded for "for his services to Theoretical Physics, and especially for his discovery of the law of the photoelectric effect".
Most of the other physics prizes are just given "for his discovery/demonstration/development of X"
siener's youtube channel
Very unsound argument. As mentioned elsewhere, the stated reason for the prize was Einstein's work (particularly that 1905 paper) on the photoelectric effect. I imagine however that Einstein wouldn't have been considered if he hadn't contributed so much more than just that work. But the observation that because objects, pets, and plants don't receive Nobel prizes, that Nobel prizes aren't given on the basis of a single act or work.
The modernized version of the formula is as follows: The amount of electronic commerce is money times speed of light to the power of two So the more money you throw at it, the more "E" you get into your business. I just love wireless networking, as I can post to Slashdot even in a seminaar!
I'd guess becuase lots of testing has backed it up, and most people with alternate theories are kooks?
If someone offers actual, repeatable proof that it is wrong scientist will listen (well some will, always get some reistance to change) until then going with what works best and has worked is what science is supposed to do.
If it is wrong, well the facts will prove it like they did with Newton's Laws.
He wrote something like E^2 = m^2c^4 + p^2c^2. Hazy memories of university physics lectures 15 years ago... Outgeeked a lot of you with that one!
Now this one I can answer, cos I've just fought my way through a term of quantum dynamics. The electron isn't in any one place, it's splurged out. It gets fluffier and fluffier until something "detects" it, at which point it coalesces. Or doesn't. That's what the "detection" process does - it decides (on a probabilistic basis) whether the electron is currently in that area of space. Of course, once it's been detected and "decayed" to a point particle, it starts getting fuzzy again.
That's the classical version anyway. The problem with it is that it's not time-independent, which messes up all those nice Einsteinian symmetries (i.e. you'd probably never be able to mesh the two theories). The more confusing version, Quantum Electrodynamics, uses a rather weird "sum over paths" approach which, by a roundabout route, suggests that our universe is predestined, but we don't know which of many many similar universes we're in (the whole "Many Worlds" thing).
Oh, and your "idea of relativity" is fluffy to the point that a real physicist would probably lose his lunch. The fact that the phrase "everything is relative" strikes a chord with you does not mean that that's what Einsteinian relativity is all about.
For the love of God, please learn to spell "ridiculous"!!!
You can. I've summarised the responses and the answer appears to be "Whooooosh!".
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
You're either full of shit or an arts major to have so little understanding of what peer review is or how it works. And your hypothesis about discoveries contradicting established findings is almost exactly the reverse of the actual situation. While you're certainly welcome to voice you're opinion, don't expect to garner any respect doing it when you obviously have no idea what you're talking about.
...it's really a sad day for America when we require a goddamn ACT OF CONGRESS to make our DVD players work properly. ~
Newton's laws aren't actually wrong. They are entirely correct within the frame of reference and resolution of the measurement devices through the beginning of the last century. In fact, one of the first big tests of quantum mechanics was that it had to collapse into newtonian mechanics at the correct scale.
I guess I agree with the spirit of your post, though.
...it's really a sad day for America when we require a goddamn ACT OF CONGRESS to make our DVD players work properly. ~
At the Large Electron Positron Collider, electrons and positrons have smashed together at energies of 200 GeV. That means that each particle has an energy of 100 GeV. Using m = \gamma m_0, and the rest mass (m_0) of an electron being 511 MeV, we find that \gamma^2 = 1/(1-\beta^2) \approx 38,300. This makes \beta^2 \approx 0.99997, or \beta \approx 0.99999.
What all this math boils down to is that the electrons at CERN-LEP are traveling at 99.999% the speed of light, which is quite a bit above 0.4!
Ben Hocking
Need a professional organizer?
Sigh. Now everything's a "podcast".
There's no subscription. There's no RSS feed. They're audio files with talking. I have a 2 hour car ride today, and I would have loved it if this were an actual "podcast" and I could have clicked one link to sync all of the audio commentary to my iPod.
Are audio files with music "podcasts" also? How about audio files with video attached?
Sorry. "You must be less than this pedantic to read Slashdot." Moving along now.
Special relativity allows me to convert mass into energy so suppose I start with a neutral pion. This can be travelling at a constant velocity when it decays into two photons. Suddenly I have now have no mass and my speed is that of light...and no external forces acted. Ooops!
Atomic decay is governed by a force in this case the electromagnetic, and thus the first law does not apply. However, because Newton defined momentum as Mass*velocity a massless photon can't carry momentum according to Newtonian theory. This is because Newton's definition of momentum was wrong due to his misunderstanding about the nature of light, not because the law was incorrectly stated. When the proper expression for momentum is used, namely the four vector of relativity Newton's second law is consistent.
First that is NOT Newton's second law...The correct law is:
The rate of change of momentum of a body is proportional to the external force applied.
This is only correct if you use the 4-vector definitions for force and momentum and not Newton's. Thus, the law as Newton wrote it is wrong.
I forgot a clause in my original statement, the phrase due to an applied force should follow change in motion. Thanks for the catch. The idea of momentum as a 4 vector only makes sense when motivated by the invariance of the velocity of light with respect to comoving observers. Newton had no reason to believe in that invariance and thus it's unsurprising he came up with a definition of momentum which is only approximately true when velocities do not approach that of light. However as you note when written with a 4 vector for momentum (which leads to the issue of which time to use to express the derivative as I noted earlier) Newton's second law is correct. Like his force law for gravity, his formula for momentum is incorrect due to his ignorance, but the law itself is fine when the correct expression for momentum is used.
first a minor point: relativity is NOT classical physics.
In the sense that relativity is not a quantum theory, and that General Relativity allows for infinite energy densities just like Newtonian physics, relativity is a classical theory. Note that when I got my first degree in physics, using Schrodinger's equation in which potential fields are also treated as fully continuous and thus allow for infinite potentials technique is referred to as semi-classical, since it bears that resemblance to other classical theories. Thus in the sense that any physical theory that allows infinite energy densities to occur is classical, relativity is classical. Or to use another common definition, any non-quantum theory of which both Newtonian physics and relativity are examples, is classical. If you want to draw the classical/nonclassical boundary elsewhere that's your perogative but since in physics the latter definition is most common I doubt you'd find many people who understand you.
One of Newton's most amazing ideas that turned out to be CORRECT was the particle nature of light
Light exhibits self interference which no reasonable definition of the word particle as used in everyday experience allows. Einstein's paper on the photoelectric effect was strong evidence of the quantization of energy of light, and quantized energy is a property of particles as commonly understood, however the reconcilliation of self interference and quantized energy is ultimately what led to quantum theory not relativity. Newton's conception of light as a particle was explicitly the idea of light as little billiard balls which is simply wrong.
Even at everyday energies Newton's laws are only approximatations and are not correct
I have no idea what your every day energy level is, but even if your total energy was 1/100th greater than your rest energy (equivalent to kinetic energy gained from moving at 14% of the speed of light, wh
Plagiarize,
Let no one else's work evade your eyes,
Remember why the good Lord made your eyes,
So don't shade your eyes,
But plagiarize, plagiarize, plagiarize...
Only be sure always to call it please, "research".
The full lyrics are available at http://members.aol.com/quentncree/lehrer/lobachev. htm. Buying one of Tom Lehrer's CDs is highly recommended, he's an extremely funny songwriter!
If anyone's interested, Richard Feynman's lectures on Einstein's special, and general relativity - for me - made its effects v.clear, and understandable [um, I think!].
... he said something like "why things tend to move in a straight line ... until a force acts ... well, no one knows" - but's that's the same as saying - 'given that motion is relative ... 'why things tend to stand still [instead of jiggling around], no onew knows!' Ok, it's common-sense *and* experience that things don't go and move about unless *forces act*, but what the heck!!!
Maybe the lack of understanding is just one manifestation of how a mind that's been subjected to 'common sense' doesn't question things. We're all *corrupt* in many ways!!
However, why it's all *just so*, neither Feynman, Einstein or Newton [or anyone?] [really] knows [no 'mechanism' is given: which was enough the Newton] - Maybe that's how it should really be???
However, one thing that Feynman said that did puzzle me
@peetm
Dude, give it up. The published paper is how the dudes on the Nobel committee (like everyone else) knew the work had been done.
"Lawyers are for sucks."
- Doug McKenzie
Firstly pion decay is not atomic decay - no nucleus is involved. Secondly you don't understand what an external force is, which you really should do if you do have a physics degree. This force is internal to the system and thus Newton's first law does apply as long as you consider the entire system i.e. both photons.
The idea of momentum as a 4-vector only makes sense when motivated by the invariance of the velocity of light with respect to comoving observers.
I'm sorry but this is absolutely wrong. Momentum is fundamentally a 4-vector. For "everyday" energy levels i.e. processes that typical people encounter in an average day an excellent approximation is Newton's 3-momentum. The motivation for using 4-vector momentum is that you have to at high energy levels (bodies with K.E. > ~10% of the rest mass energy) otherwise you get experimental results inconsistent with conservation of momentum. It was historically discovered through the path you describe but there is no requirement that be the case. Had Einstein not been born accurate measurements of high energy electron momenta would also lead to Special Relativity. Einstein's genius was that with a tiny amount of data he lept to the right conclusions. But realtivity is way more important than just talking about the speed of light in two intertial frames.
In the sense that relativity is not a quantum theory...
Depends on your definition of "classical" physics. The one I use, and I believe is the most common one, is physics based on Newtonian mechanics. SR is non-Newtonian and therefore non-classical. It is possible that my definition is not as common as I think but you'll have to excuse me if I don't take your word for it.
Light exhibits self interference which no reasonable definition of the word particle as used in everyday experience allows.
That is where quantum physics comes in. Light is indeed made of "particles" or quanta called photons. These do not behave like ordinary everyday particles but nevertheless are referred to as particles because of their localised nature.
Given that few people have ready access to equipment that measures time or distance to better than six significant figures the relativistic correction is indistinguishable from measurement error.
I'm glad you agree, that is PRECISELY my point! They are approximations. I'll grant you they are very good approximations (which is why they held so long) but approximations nonetheless.
Which leads to my point that Newton was correct for what he was capable of knowing.
What exactly does this mean? He was "correct" because he didn't know he was wrong? So does that mean the only time you are ever wrong is when you are capable of knowing you are? If so perhaps you'd better brush up on the meaning of the word "wrong".
Neither was there any reason to suppose that they were true. He certainly had no experimental evidence to that effect. That was a mistake, an easily forgivable one but still a mistake....and mistakes lead to being wrong!
Newton's formulas, which are to be distinguished from his laws...
Why exactly? What you are saying here is that if you take Newton's words, redefine the physical quantities to the SR expressions and keep calling them the same thing then he is still correct. i.e. if we redefine the bits that Newton got wrong the rest still works! All you have done is said that instead of getting the laws wrong Newton got the definitions of momentum, acceleration and force wrong.
This is pure semantics either I redefine 'F' and 'p' to keep F=dp/dt or I keep 'F' an
Wasn't that the whole point of Einstein's paper, though? That only the atomic hypothisis could explain Brownian motion?
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
Yes, but that's not a logical deduction. That's a conclusion based on the assumption that Brownian motion is true, something seen by experiment. There is no a-priory way by which the existence of atoms can be deduced (like the parent implied). IF that were possible, then people would have figured it out long before Einstein and/or Thompson.
l'Homme n'est Rien l'Oeuvre Tout: Gustave Flaubert to George Sand
You're right about the state of fusion energy development. But your fuzzy smear of "some environmentalists" is unsupportable. Sure, some people think all E=mc^2 ever achieved was "The Bomb". Most people who ever heard of it, in fact. Most of those people aren't "environmentalists", who "obstruct progress through protesting etc". Most of those people are driving 10MPG SUVs alone to the grocery store, throwing their wrappers out the window. Though they do mostly say they care about the environment more than they care about, say, perpetual war in the Mideast.
It's true that the matter/energy conversion physics also achieved peaceful fission power plants. Which produce the most toxic substances known, administered by often hapless, unaccountable corporations with government-guaranteed profits, regardless of the actual economics. Whose products, apart from electricity, pose a tremendous security risk, while leaking poison into our bodies. The actual environmentalists who actually do something to protect us from the total abuse of this tech are generations of people responsible for the fact that you're not a cancer casualty yourself, along with 100x the Americans who are anyway.
Your derision of their "whatnot" is a disgusting disrespect for people who have spent their time working to keep our lives safer and cleaner. Instead of just cheerleading along to early graves, surrounded by the industrial pollution that you can't seem to get enough of. Without the safe environment we've managed to secure, despite the odds (and people like you), we'd never live to see the days when we'll bring our environment to other worlds. Where we'll get a chance to jeopardize those environments, too. If we were just chained forever to a canister of plutonium, rather than the occasional tree, we'd never get anywhere.
--
make install -not war