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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."
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
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.
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?
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.
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.
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!
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
Well, one example of where Netwon fails is explaining the rotation of the planet Mercury around the Sun. Since the gravity is so strong that close, Netwon fails, and we must use General Relativity. I believe the planet's orbit (someone correct me) actually spirals.
Anonymous Cowards suck.
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
This word "anonymous." I don't think it means what you think it means.
All this business of E = mc^2 "giving us the nuclear bomb" is another example of newspaper pap-science. There's far more to a nuke than computing the mass defect.
The whole idea is a staple of Relativistic kinematics which has been verified in collider experiments, etc., etc.
You can define relativistic stuff in less than four dimensions (e.g., one of space and one of time). Take an electron-positron annihilation into two photons. A proper treatment requires quantum field theory, where mass can be understood (in one way) as a parameter constraining the dynamically allowed momentum-energy configurations of the physical ("on-shell") fields. It's [probably] not right to think of electrons as little dots of mass.
Again, you need to consider quantum field theory to [begin to] answer these questions.
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.
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
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.
I would recommend reading:
Relativity : The Special and the General Theory
By Albert Einstein
This is written for the technically inclined layman. I read it and since then I've been life of the party. It really did make things much more clear - like what does flexible of spacetime have to do with the speed of light? It's all in there!
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
100th anniversary? Yeah, but it's all relative
First thing to realise is that there are two theories of relativity - special and general. Special came first, is much easier to get your head around, and concerns motion, energy and that equation. The second, general theory came after, concerns gravity and is a complete pig to work with (Riemann curvature tensors anyone?)
As to why does it matter, the equation shows how you can convert one to the other, how things get screwy as you approach c, and tends to come up and bite you when you follow a perfectly reasonable line of Newtonian reasoning forward and find it ends up complete gibberish. In such circumstances you learn that yes, it does occur in real life, and it helps if you understand it.
Einstein noticed that there's a discrepancy between Newton's laws and Maxwell's laws of electricity and magnetism (E&M). To patch this, most physicists assumed special treatments for E&M like ether. Einstein went backwards and decided Newton must be wrong.
The most amazing conclusion he reached was that the speed of light is a constant in any reference frame. ANY reference frame. Even if you were moving at 1,000 million miles per hour, the light will still travel at the same speed to you as if you weren't moving.
To me, to have the audacity and creativitiy to challenge Newton and come up with absolutely mind boggling conclusion like the constantcy of the speed light are the most amazing thing about the special relativity.
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
Floats? Have you never heard of quantum mechanics? Duh!
God does not use rand() on the universe.
Plenty of things travel at the speed of light. Just no things with mass != 0.
I don't know if I fully believe that energy equals mass... To take mass, and BANG, the mass is gone and there is energy, does not ring true to me.
And Newton's first law of motion didn't ring true to Aristotle—clearly objects in motion tend to come to a stop if nothing is pushing them. Our intuition about how the universe works is based on our limited experience of medium-sized objects moving at low speeds on the earth's surface, with the result that all physics post-Aristotle is more or less counterintuitive. The fact that you can't imagine it doesn't mean it isn't so.
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!
(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?
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....
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 . . .
Wow, that's awful. When you burn something, no matter is converted to energy. The amount of energy released in a fire is nowhere near enough to actually cause nuclear reactions, which are needed for mass changes. When something is burned, what happens is that chemical bonds are released, giving up their energy. The weight of the burned object seems to decrease because the principal byproduct of fire are gases and ashes, both of which float away into the atmosphere.
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.
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]
I realize it's gauche to reply twice to the same comment, but there were a couple things I didn't answer:
What did E=MC2 give us the past 100 years?
It's a fact (approximately) about the nature of the universe. It doesn't need to give us anything. What did the discovery of the planet Neptune do for us? Nothing practical, but I think knowledge is worth seeking for its own sake.
What I think is more useful from E=MC2 is the idea of relativity. It is true, not just for science, but for almost every field of study.
If by "the idea of relativity" you mean, roughly, "there are no privileged inertial frames of reference", then I have a hard time imagining what bearing that idea has on, say, art history, or comparative religion. If you just mean that "everything is relative", then I'd say that your idea of relativity has very little to do with Einstein, and is probably too vague to be much use in any other field, either.
> 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.
Not only does God definitely use rand() on the universe, but He sometimes confuses us by seeding it with /dev/random.
Welcome to the Panopticon. Used to be a prison, now it's your home.
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?"
Nope. Grandparent is completely correct (even though he says he's not in a later post). Burning is exactly analogous to nuclear reactions. Bonds are broken and energy is released. In both cases, matter is converted into energy. It does not matter whether the bonds are electromagnetic (chemical) or strong (nuclear).
.04 milligrams.
In chemical reactions, the amount of mass converted to energy is very small and nearly impossible to measure, but that's not the point.
Example: To heat your house, you use on order of 1000kWh per month, obtained by burning natural gas. 1000 kWh = 3.6 * 10^9 Joules. E=mc^2, solving for m: 3.6 * 10^9 J / (3 * 10^8 m/s)^2 = 4 * 10^-8 kg =
My credentials: I'm a graduate student in physics at the University of Minnesota.
Doggone it! Did I get snookered by a wonk? Thanks for the follow up. I'll be sulking in the corner.
Michael.
Linux : Mac
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.
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 :)
...the greatest physics jokes collection. Lots of other science jokes there as well.
From the sound of it, it seems that De Pretto wrote the equation and had no idea what it meant. I'm a total layman when it comes to physics, but it seems entirely possible to come up with something profound and not have a clue if it's true or not.
So Einstein might not have written the equation, but he obviously figured out what it meant and that's really more important, isn't it?
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...
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.
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
Confucius say, "Find worm in apple - bad. Find half a worm - worse."