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No Time Travel, Sorry
MOBE2001 writes "The bad news is that time does not change. Spatial velocity is given as dx/dt. Velocity in time(dt/dt) is nonsensical. As simple as that. In other words, no time travel to the past or the future, no motion in space-time, no wormholes and no hanky-panky with your great, great grandmother. There is only the changing present, aka the NOW. The good news is that distance is an illusion and we'll be able to travel instantly from anywhere to anywhere."
How else could people post articles in The Mysterious Future?
Karma: SELECT `karma` FROM `users` WHERE `userid`=138474;
That's weird because I could have sworn when I went to bed last night it was yesterday and now its today.
Nevertheless...this is fun. Looking at the equation from which all his arguments flow, it seems he is only demonstrating that it doesn't make sense to talk about one's velocity through time. I would agree. If I hop in my time machine and zip off to tomorrow, it doesn't make much sense for you to ask how long it took to get there. Or if you and I both have time machines and we decided to race to 1:00 pm tomorrow it would be always be a tie. But this is a far stretch from demonstrating that it is impossible. By this same logic we could define slope as the change in x over y or s = dx/dy. Does this definition make it impossible to move along the y axis because then the slope of our movement would be dy/dy? No. but it does say that if you move along the y axis your slope will be a constant.
(Seriously. It's like he read Zeno's Paradoxes and it blew his mind, man.)
Obliteracy: Words with explosions
But in all my readings, I have learned one thing about physics. Nothing is "as simple as that".
--dave
davecb@spamcop.net
This guy is a pseudo-scientific moonbat. Please don't waste your time with the not-so-FA.
Helium balloons want to be free.
... because we already know everything there is to know about the universe
As Ford Prefect put it, "Time is an illusion, lunchtime doubly so."
This sig, aah-ah, is comin' like a ghost-sig...
Do they use the Back to the Future method or the Bill and Teds method of time travel?
Also, did they attempt to spin the Earth backwards on its axis? I heard that works if there is a lady in distress.
I'm sorry, but if you're going to put up a web page in which you call all the foremost theoretical physicsts in the world frauds, then you'd better have more evidence than some undergraduate-level pseudo-calculus and verbal smoke screens.
The t-axis or time-axis velocity component is 1, a dimensionless number. Now there are relativists who will insist that it is perfectly acceptable to express velocity in time with a dimensionless number but the rest of us with our head on our shoulders, know that it is not true. We know that a dimensionless number such as 1 has absolutely no meaning in as far as expressing velocity.
Not true. Normalized velocities are perfectly reasonable things to express. Mach 1.25 is a perfectly well-defined speed that does not violate any laws of physics, and what do you know--it's a dimensionless number.
I'm sorry, but this page is really quite embarassing for the author's parents and any physics teacher's they've ever had. This sort of reminds me of people that read things like A Brief History of Time, a perfectly excellent book, and then try to tell me that the physics is really great and it would be so much better unencumbered by the mathematics.
I don't think real time travel, a-la Dr. Who is physically possible. But the "arguments" on this web page don't really make sense, much less prove all those physics wrong.
Craig Steffen
Ph.D. Physics, Indiana Unversity, 2001
Craig Steffen
http://www.craigsteffen.net
HA! Take this from a person who has been in a long distance relationship... The distance is a reality, the relationship is the illusion.
We really outa get these theoretical scientist types out of a lab for a beer.
Victory is gained, not in knowing your opponents next move, but in preempting them.
That's it. I'm going to write a letter of complaint to Michael J. Fox and Christopher Lloyd to express my disgust at being deceived for the past 20 years.
A Deloreon, a flux capacitor, 1.21 gigawatts of power, and enough road to get up to 88 miles per hour.
Corporatism != Free Market
Going forward is easy. The hard part is not dying.
I did what?
Discounting the obvious fact that each and every one of us are traveling into the future at one second per second, time travel into the future is a proven fact-- if you define "time travel" the right way. That is, if you define "time travel" as "moving at some velocity significantly different from one second per second through time", rather than "instantly POOFing from one time to another", "time travel" forwards is as simple as traveling at high relativistic speeds.
With spending like this, exactly what are "conservatives" conserving?
-1, Nutjob
www.code-fix.com
I'm from the year 3042. We have found that time travel is real, and would have discovered the time machine in 2048, but scientists were detered by this article.
Dan Church is Wicked Ill
Help Fight SPAM today!
Does this mean then that there is no waiting till tomorrow to see what karma your Slashdot post generates, then zipping back to yesterday to fix it, before returning to today to relax knowing what karma your Slashdot post will have generated by tomorrow?
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
Time travel, remember? YOu haven't done it yet.
I still have more fans than freaks. WTF is wrong with you people?
Spatial velocity is given as dx/dt. Velocity in time(dt/dt) is nonsensical.
That would be a lovely argument if changes in position were measured in velocity.
You describe spacial travel as the dx, not the dx/dt. It stands to reason that you would describe time travel with the dt, not as some rate of travel we haven't come up with yet.
Go into your closet, and bring enough food and water for 5 years.
Now wait...and eat sometimes.
5 years later, exit the closet.
You will find that time of the world has advanced from when last remembered by 5 years.
PS. don't forget to setup an auto-pay for your residential rent/payment. Otherwise your travel may be interrupted, and you will not be able to travel the full 5 years.
The people who wrote this article also wrote this... " I will argue that the messages to the seven churches of Asia are a metaphorical description of the organization and operation of the brain. I will further argue that the golden lampstand (Jewish menorah) symbolizes a seven-node sequence in brain memory." Hmm, it certainly is curious that the author of the article is not revealed. Probably some first year calculus student who was like "Holy guacamole! dt/dt = 1, Einstein and Hawking are crackpots! I must tell the world!"
Then again, maybe I should just "laugh, it's funny"...
This guy is good, but he's not nearly as entertaining or mind-warping as the TimeCube guy. Four days in one!!!
- Give a man a fire and he's warm for a day, but set him on fire and he's warm for the rest of his life.
This guy is clearly an Evil Ass Educator aiming to suppress Time Cube,
and only dumb ass students condone such evil. Cubeless institutions are spreaders of evil, and students lack mentality to challenge it.
"Joke" foot on article: check.t mp ace
Suspicious URLs:
http://www.rebelscience.org/Crackpots/notorious.h
http://www.rebelscience.org/Crackpots/nasty.htm#S
Check.
Comments taking the article 100% seriously: check.
This must be Slashdot.
OK, let's say that you and I race to 1:00pm tomorrow. You decide to stay right where you are and wait for 1pm to arrive. I, however, jump in my ship for a trip around the solar system at relativistic speeds and meet you there. When 1pm comes around we are both there, but you've aged like 24 hours while I've only aged a couple of minutes. I would say I have won because it took me less time to get there.
-- Thou hast strayed far from the path of the Avatar.
Everyone agrees that practical time travel is at the very least exceptionally unlikely. But whether our model of the universe excludes the posibility of time travel is another matter entirely.
Note that even if our model of the universe allows for time travel it does not mean that time travel is possible. Not least because we know that our model of the universe cannot possibly be completely right. Quantum physics provides an excelent model of the universe at a large scale, relativity provides a good model at the cosmological scale. The problem is that the two models are incompatible. At leas one of our models must be wrong. Most likely they are both approximations.
The other issue that the writer does not seem to grasp is that the ability for matter to travel through time and the ability of information to travel through time are very different issues. For meaningful time travel it has to be possible for information to move backwards in time and not just matter. Otherwise what would come out the other end would be a random soup of quantum particles, not the time traveller. This is the problem with black hole time travel, the most that can come out the other side is a random soup.
The 'proof' provided by the author only demonstrates that he does not have the slightest understanding of the subject he is pontificating on. dt/dt = 0??? No, all that shows is that the dimensions of the two quantities are the same. Besides x/x = 1 in most algebras.
Looking for an Information Security student project suggestion?
Try http://dotcrimeManifesto.com/
Slashdot, I have traveled back in time seven days to warn you that you will be duping this post. Please make sure this does not happen. Oh, and the post after the dupe is a counter post, which says time travel is possible, and will be used to let you know of your dupe. Take care.
saboola
It took less time as you observe it. To use one of the standard ways of explaining relativity: there are two astronauts. One stays on Earth to train, while the other goes on a mission, zipping around the solar system near the speed of light. When he returns, he aged 1 month, while the astronaut on Earth aged 1 year. What gives? Well, the same amount of time "happened." Both spent one year on their individual tasks. The one that went on the space missions feels like one month passed, but that's just because of how he observed time. Time is constant. Time did not pass at different speeds.
Another way of thinking about it is driving along a highway, watching a mountain, forest, clouds, or some other large object at a distance. Nearby objects appear to move faster relative to your car, while the farther away objects appear to move slower. The road sign and the mountain are both standing still, but appear to move at different speeds relative to your car. This is similar to time. You may observe different events at different speeds, or two astronauts may observe the same event at a different speed, but time itself is constant.
24 beers in a case, 24 hours in a day. Coincidence? I think not!
We can take the differences between this guy and the time cube guy as one vector, and the differences between this guy and Archimedes Plutonium as another.
Now that we have two basis vectors, we can define a two-dimensional phase space for crackpottery instead of relying on scalars.
Now that we can apply some basic vector and tensor operations to the field of psychoceramics, think of the new discoveries to be made!
U rong, he rite. Ugg smash bad math.
Mach (X/S) * (S km/s) = (X km/s)
S = speed sound
X = speed ugg
Ugg no listen reply. Ugg finger stuck ear.
I just came back from the future and ... this post was duped 4 times!!
So my best guess is you were 10 hours ahead?
Seven puppies were harmed during the making of this post.
You have to use Christoffel symbols. Whip out your favorite copy of differential equations in curved coordinate systems, or read up on it here: http://en.wikipedia.org/wiki/Curved_spacetime
You're wrong. For the guy who travelled at the speed close to C time did slow down. Let's say that at the onset of the journey both planted a bonsai tree that grows at 1 inch per month. Upon the reunion, the earthbound astronaut's plant would be 12 inches tall while the traveller's plant would be only 1 inch high.
Your pizza just the way you ought to have it.
If "time travel" just means the usual physics definition of "tracing a trajectory backward" then of course you can regard it as happening all the time. Positrons (anti-electrons) can easily be regarded as electrons traveling "backwards" in time, so that a positron-electron annihilation event is nothing more than an electron traveling "forward" in time, then reversing itself and traveling "backward" in time. Obviously we (traveling steadily forward in time) see two particles with opposite properties converge and disappear. Whoopee.
However, I think what most people mean by "time travel" is something different, a causality loop. That is, they mean you do something (which they call "time travel") and this something lets you become your own grandpa, or influence the outcome of the Civil War, and so forth. Since, of course, those things influence the you that's influencing them (otherwise the story is not interesting), this makes a nice little loop of cause and effect: you influence x which influences you who influences x, and around and around.
Whether or not the physics of the universe allows such a thing, I can't see any obvious reason why it would cause big problems -- or even be interesting. Certainly it could not manifest itself the way it's shown in the movies, in which you see the loop first one way (Marty McFly's parents marry and produce him), and then another way (Marty's parents fail to marry, because McFly travels back in time and interferes with their meeting). That's logically impossible. If the loop exists at all, it must have one unchanging form.
That is, if Marty McFly does go "back in time" he obviously can't (or rather doesn't) prevent his parents from marrying and having him, because they actually did. Whatever he does "back in time" is already part of history. His "changes" already exist, and have always existed. Indeed, they can't even logically be regarded as "changes" because nothing really changed. Although...it's possible McFly, with his imperfect knowledge of the past, could have assumed something about the past was different than it actually was (e.g. he thought his parents met at the dance, instead of afterward, when some strangely-dressed clown introduced them). Therefore, when he "changes" history (by interfering with his parents meeting during the dance, and then "fixing" things up by introducing them afterward), he might be under the illusion that he is really "changing" history instead of simply causing it to happen as it actually did.
I suppose we could now argue about whether Marty's sense of free will (as well as our own) is therefore just a big fat self-delusion, but, ugh, not before a pint or two.
No. You misunderstand the twin paradox: the twin that journeys will age less than the twin that stays behind in the classic "paradox".
The two frames are not inertial frames since one twin accelerates during the experiment. While the result is no doubt peculiar, there actually is no paradox to resolve.
You can read all about it here:
http://en.wikipedia.org/wiki/Twin_paradox
Life is short: void the warranty.
Haven't read the article thoroughly, but the author seems to confuse to concepts in Relativity:
The four-dimensional speed is defined as d(t,x,y,z)/dtau, not d(t,x,y,z)/dt, so the first component is dt/dtau, not dt/dt = 1, as the author suggests
This mistake invalides the whole article.
From http://www.rebelscience.org/Seven/bible.html:
;-)
(S)He writes:
"I started working on Animal (around 1995; see history) years before I formulated my biblical hypothesis. As I get more and more confident about the accuracy of my interpretation of the biblical metaphors, I will incorporate my findings into it. I hope to have it learn the game of chess on its own, including the rules of play. If my hypothesis is correct, there is no limit to how competent the program can be at playing chess. "
Do I really need to give a context?
(I hope I don't somehow offend any Christians out there- I've never heard of a denomination that believe's Jesus' real message was how to win at chess...)
No: we actually travel through time at slightly different rates all the, er, time. We just don't notice it because the effect is so small under normal conditions.
The passage of time varies with velocity and the presence of gravitation fields. You can actually measure the difference using atomic clocks. Both clocks will pass through the same points in time, but at different relative times. That is, when you bring the clocks back together you will find they have a discrepancy that is due to the difference in velocities and gravitational fields that they experienced while apart. This test has been done many times and the results are completely in agreement with General Relativity.
Life is short: void the warranty.
I too cannot tell if this link is serious. If you want to read a good explanation of the current understanding of time, check out Brian Greene's article "The Time We Thought We Knew" from the 1/1/2004 edition of the New York Times. (note: if you don't want to pay for it from the Times, you can get to it through your local library's website under their public databases, if you have a library card/account.) Greene says, "catapulting yourself forward in time is beyond what we can now achieve, but scientists routinely use high-energy accelerators to propel particles, like electrons and protons, to nearly the speed of light, slowing their internal clocks and thereby sending them to the future. Though unfamiliar, forward time-travel is an unavoidable feature of relativistic reality." He goes on to explain what time is and ends by saying, "And in moments of loss I've taken comfort from the knowledge that all events exist eternally in the expanse of space and time, with the partition into past, present and future being a useful but subjective organization."
One thing I think I should point out about how spacetime doesn't fit the general model of a 4-space, and it's simple:
Object do not pop in and out of existence as time progresses.
If time were simply a velocity in a dimension in a 4-space, that could happen. Instead, we see a continuity in 3-space, where an object might move, but there is a relationship between where it "is" and where it "was" and where it "will be".
So, it makes sense to model spacetime as a 4-space, but not as a general one.
This dude clearly has no idea what he's talking about. Especially when it comes to differential geometry, which is paramount to the theory of general relativity.
He claims (t,x(t),y(t),z(t)) is a 4-manifold, which is just not true. It's actually a 1-manifold embedded in 4-space. The whole point of writing "x of t" is to say that x is completely parameterized by t. So while this describes something that lives in 4-space (you could actually argue that it lives in 3-space since the dependence on t is trivial), it is completely parameterized by t. Think of a function in the plain - a set of points (x,y) such that y = f(x) (or vice-versa). While the function is embedded in 2-space it is only a 1-dimensional manifold: the entire point is that we can completely specify y in terms of x.
If we place that large restriction on our space, then it's no surprise that "dt/dt" (which is basically nonsense, but we'll assume he means the derivative of the identity function applied to t with respect to itself) is equal to 1, and that the dimensions are "seconds per second". What we really care about is the pull-back of the differential form through the t parameterization: dt + (dx/dt)*dt + (dy/dt)*dt + (dz/dt)*dt. Furthermore, this only makes sense if t lies in a connected region and is single-valued. So if we travel in time from t = now to t = future, then the differential fails to exist.
I thought he might just be goofing off, but if you look at the other crap on his website and his slashdot comments, it seems this guy really is full of crap. It's scary that he's asking for money for this stuff.
m0nstr42.blogspot.com
I just flip the page. Same with Newsweek.
"National Security is the chief cause of national insecurity." - Celine's First Law
_Special_Relativity_ says that two observers moving past each other in unaccelerated reference frames will each perceive that the other's clocks are running more slowly. The observations are consistent. To get the two observers into the same reference frame, one or both of them would have to accelerate, and general relativity conveniently works it so that the paradox vanishes.
In the actual example, one observer is remaining stationary, while the other is accellerating to high velocity, then accelerating to change velocity ("around the solar system") and then presumably accelerating a third time to return to the original reference frame. All three accellerations, plus travelling at high velocity relative to the rest frame, will cause the traveller's clock to run more slowly, as observed by someone in the rest frame.
time dilation can be reproducably created, and in fact occurs on a daily basis, to a slight extent every time someone flies an airplane, or is launched into orbit aboard a space vehicle. technically just 'walking' will create a small bit of 'time dilation' it might be impossibly small to try and detect, or course.
;)
Nasa has done a lot of research on this. if you accelerate a physical object to the 'speed of light' it's 'relative' time stops in comparison to that of the universe, while time continues to flow for the rest of the universe, until that object is decelerated to normal velocity.
So if 'time' can't be traveled through, then what exactly is 'time dilation?' Also, black holes are only useful for traveling 'forward' in time, the 'intense gravity' within a black hole 'simulates' traveling forward at the speed of light, the closer you are the greater the gravity, and thus the greater the time dilation. no one has formulated or demonstrated the possibly to go 'to the past' although if 'gravity' and 'light speed travel' can decelerate ones own flow of time so the future can be reached, then 'anti-gravity' or some form of 'reverse momentum' might perhaps allow one to experience a pocket of time where as one progresses through it the entire universe grows 'younger' the problem with this is gravity and acceleration seem to both follow temeperature and have a common starting point or 'absolute zero' below which it is impossible to go.
appologies to all the great science fiction, but traveling back in time just isn't possible.* (unless of course one travels forward through time throught the end of the universe as we know it, until a new universe is created from the ashes of the old one, assuming that that Does in fact happen, and given the nature of atomic mass to develop in a consistant patter, one travels to the 'future' of a new 'third world inhabited by the evolutionary decendants of apes' before they manage to create time travel, and knowing exactly how the universe unfolds (because of a massive quantum computer and impressive algrythm that can determine the exact course of events Before they happen, again, based on the data it recieved while you were traveling 'forward' in time...) and thus influence the development of a primative world that the locals call 'earth' because everything formed along the same 'predestined' pattern based on the arrangment of molecules in the universe when it collapsed... only you went and went Forward in time, causing the end of the universe to happen differently than when it ended last time, so now you're ona world inhabited by 27 foot tall sentient lizards who think mamals are a tasty snack.
oops. well, you shouldn't have tried to avoid the big crunch to see how the universe would unfold the next time around
https://www.gnu.org/philosophy/free-sw.html
I believe that you may be labouring under a misunderstanding of spacetime. I suggest that you look for the text "Spacetime Physics" by Wheeler et al. as it explains this from first principles in simple language and backs this up with (initially) easily comprehensible mathematics. Time dilation occurs and is why synchrotrons are able to produce the high frequency output that they do. It is measurable, repeatable science and is now used for a commercial purpose. We are well past experiment or theory on this. Time dialtion is also critical in the explanation of several observed astronomical phenomenon. But we should be thankful for the website. Any challenge to the accepted is a good thing and allows us to grow in our understanding.
That's not my point. I'm saying that while time appears to go slower, it didn't actually speed down. Sure, the tree grew more slowly, but that doesn't change the fact that time itself did not.
24 beers in a case, 24 hours in a day. Coincidence? I think not!
I wonder what his crackpot index would be?
Try a Google search for "nothing moves in spacetime".
Is your quantum giving you trouble? I'll work on all quanta, foreign or domestic! I've got a fully loaded Snap-On tool chest, some dirty coveralls, a couple of Schrodinger's cats, an air wrench, and a singularity compressor. You can trust me to treat your quantum with the greatest of care, and I promise I won't put metal shavings in your finite square well transmission when you're not looking. Plus, you'll get the best warranty in the business, valid in all 50 eigenstates!
So, if you see some maintenance on your event horizon, give me a call!
In Soviet Russia, I can think of a few ways I'm going to abuse you!
<xml><I><am><so><damn>Web 2.0</damn></so></am></I></xml>
Dear Rob
...@steel.ucs.indiana.edu (Gregory L. Hansen) wrote: , ...@indiana.edu wrote:
I'm sorry to have to tell you but you've been scammed by a well-known internet kook called Louis Savain into slashdotting his junk
If you google for "nothing moves in spacetime" and "rebelscience.org" you'll find lots of references to this particular paranoid schizophrenic (no, I'm not kidding)
He likes to spam sci.physics and sci.physics.relativity with his junk. One of his recent postings is fairly typical:
On Sun, 22 Jan 2006 16:59:17 +0000 (UTC),
glhan
>In article
>Traveler wrote:
>>On 22 Jan 2006 07:55:33 -0800, glhan
>>Repeat after me: NOTHING MOVES IN SPACETIME.
>World lines don't move in spacetime. When people talk about the motion of
>a particle they refer to a succession of points on the worldline, not the
>worldline in its entirety.
Repeat after me: ABSOLUTELY NOTHING MOVES IN SPACETIME!
NOTTHIINGGG!!!!
What this means is that there is NO CHANGE in spacetime (that's why it
was called Einstein's block universe by Karl Popper) and spacetime is
a fictitious math construct with no counterpart in reality. Now, isn't
it a tad weird that your idol Einstein agreed with his friend Kurt
"lunatic" Godel when he announced in 1949 that the spacetime of GR
allows time travel to the past via time-like loops?
Now hold on a southern cotton picking second! Aren't Kurt Godel and
Albert Einstein revered by physicists as two of the smartest men that
ever lived? Yep. ahahaha... One then wonders how they can be so stupid
as to believe in motion in spacetime. ahahaha...
http://www./ rebelscience.org/Crackpots/notorious.htm#Einstein
ahahaha...
>>> Or that your alien-induced lattice that exists nowhere is
>>>also an abstract model of your invention?
>>Nope. My lattice is not made of abstract crap but of real particles.
>>You crackpots call them virtual photons. ahahaha...
>You have a model that describes a lattice that is not made of abstract
>crap. You're like the screen writer who writes a line like "This isn't a
>movie, you know."
Maybe in your imagination but I know one thing: I am not an ass
kisser. I do my own thinking, than you very much. ahahaha... And
that's the way I like it. ahahaha... AHAHAHA... ahahaha...
Physics is so much phucking phun! ahahaha...
Louis Savain
Why Software Is Bad and What We Can Do to Fix It:
http://www.rebelscience.org/Cosas/Reliability.htm
I would suggest you remove the story
Tubby or not tubby. Fat is the question
I'm uncertain about my position on this...
But since the universe is expanding at such an incredible rate, when somebody goes back in time, it is not to the same place on earth, which is moving at something like 300,000 kps along with the universe, but they stayed right where they were. Just a thought. Everybody always assumes time travel is always tied to a relative location not an absolute one.
But the whole point is that time did move slower for the guy in the spacecraft. The two reference systems are not symmetrical (you seem to be confused by this fallacy). The time flowed 12x slower for the guy in the spacecraft. Read up on the "twin paradox" and why it's not a paradox at all.
Your pizza just the way you ought to have it.
The article creator sould look into string theory-they are cruising at 11 (or 10) dimensions (haven't checked lately, may be out of date but definitely down from 26!) for spacetime, so it is quite possible for time to be a function of other dimensions (or be totally bypassed in one or more dimensions).
This is the kind of nonsensical reasoning that the NeoCon Nazis are using and that we were taught to avoid in elementary philosophy (logic course): remember proving 1 = 2?
Supreme Granter of Doctor of Obviology Letters ("A FIRM Command of the Obvious")