100 Years of Special Relativity 299
phrotoma writes "Wikipedia notes in their Selected Anniversaries section that today marks
the 100th anniversary of Albert Eintein's publication of the third of his four Annus Mirabilis Papers entitled On the Electrodynamics of
Moving Bodies; the seminal work that introduced the concepts which would come to be known as Special Relativity. This
event is also being commemorated in a UN endorsed celebration of physics: World Physics
Year 2005 with talks and events at public schools, museums, and universities the world over."
100 Years (Score:5, Funny)
Re:100 Years (Score:2)
The first five posts are all riffs on the same theme -- dilation of time. Does that say more about the level of education among Slashdotters, or about our lack of creativity, or both? I guess it's all relative.
Re:100 Years (Score:5, Funny)
> The first five posts are all riffs on the same theme -- dilation of time. Does that say more about the level of education among Slashdotters, or about our lack of creativity, or both?
Maybe it's just one post arriving via gravitational lensing.
Re:100 Years (Score:4, Insightful)
So we have kids, desperate to get a +5 funny to validate themselves, on an article they know nothing about. So what do they do? They try posting something 'hilarious', like a play on words of something in the article, or something starting with 'Did anyone else read this as...', or a reference to one of the tired slashdot memes, as if quoting Douglas Adams makes them one of the Slashdot 'in crowd'.
It ruins it for the rest of us, as on any science article, we have to scroll half way down the page to get to the first person who actually says something relevent to the article.
Re:Why we all thought of Time dilation immediately (Score:3, Interesting)
Well, this is because the fundamentalist wackos don't understand it at all. They don't understand evolution either, but they at least have a BS version of it to bash. Although, I have seen a few fundies mention that the theory of relativity is "only a theory" whereas the laws of thermodynamics are "laws" and thus somehow help their arg
Re:Why we all thought of Time dilation immediately (Score:3, Interesting)
Alas, that isn't the case [creationism.org].
Re:Why we all thought of Time dilation immediately (Score:2)
"The real point is that these jokes were modded up."
It's still a matter of relative time - or actually timing. 200 posts down the thread you get nothing for the same joke - unless of course the 'observer' begins to read at that point and then...I think it's got something to do with the Great Wheel of Karma.
billy - if two trains...
Re:100 Years (Score:3, Interesting)
Re:100 Years (Score:3, Interesting)
Re:100 Years (Score:4, Funny)
Re:not 50!! (Score:2)
Well, there's general relativity which is really the big step forward IMHO. And then there's the development of quantum mechanics.
Pffft (Score:5, Funny)
Re:Pffft (Score:2)
Like it was only yesterday (Score:2, Funny)
No, not Einstein (Score:3, Funny)
Eurocentric insensitive clods!
Re:No, not Einstein (Score:2)
Can't pull any fast ones on you, Can I?
You didn't just fall off the turnip truck.
Re:No, not Einstein (Score:2)
I agree. On Slashdot people never get that your post is making fun of itself. Not the first time a truly humorous post has been rendered mostly unfunny by a tiny error.
I just couldn't think of a better way to word it. I almost went with "anglocentric", which in hindsight would have been better.
Plus I said "to slow" instead of "too slow".
Depends on How You Look at It (Score:4, Interesting)
I just cant resist (Score:2)
Re:Depends on How You Look at It (Score:5, Informative)
First of all you're only referring to special relativity here, which ignores acceleration and gravity. Secondly, there were still some leaps of faith to be made, such as assuming c is constant in all frames of reference, which Lorentz showed non-Newtonian transformations that would allow this for Maxwell's equations. And expanding the new energy definition and concluding the zeroth-order term (mc^2) is the rest energy of mass also took another leap of faith (although that paper wasn't published until a few months after this first relativistic one).
But even so, discovering the connection between relativity and E&M is still amazing, in my opinion. For examle, the permittivity (epsilon_0) and permeability (mu_0) of free space are two constants that can be measured in the laboratory rather easily. Yet Maxwell's equations in vacuum describe waves travelling at speeds 1/sqrt(epsilon_0*mu_0), which is exactly the speed of light in vacuum (although in Gaussian units this connection is far more obvious). It's pretty amazing to think how these are related. But you still need to make some assumptions to get the Lorentz transforms between reference frames.
Additionally, even simple special relativity was extremely controversial, it rejected many assumed notions of space/time. There were also many paradoxes that took awhile to get ironed out. Many scientists didn't believe in relativity until it was shown in experiment. And in fact the theories of relativity were so controversial that the Nobel committee didn't want to award Einstein the prize based on these, so went for the safer 'Photoelectric Effect' instead.
And thirdly, general relativity, although again not included in this 100 year anniversary, is total genius, and it took Einstein 10 years to come up with the theory. So don't wave off relativity as just a 'refinement of Maxwell's field equations' because it really is much more than that.
Re:Depends on How You Look at It (Score:2)
Re:Depends on How You Look at It (Score:3, Insightful)
Well, we are discussing special (not general) relativity. General is a magnum opus. But we might have a merely semantic disagreement, which does reflect in different standards for "genius". I mean it quite literally, "the origin or source". Special relativity was an evolution of Maxell's fields, and General relativity was an evolution of Special. Even the equivalence of gravity and EM was implications of those progressive developments. Often it is a novel implication that is more valuable
Re:Depends on How You Look at It (Score:2)
If SR was just a tippy-toes extension of maxwell's laws, as
Re:Depends on How You Look at It (Score:2)
I consider Einstein himself a genius. Because his vision of the universe, fro
Re:Depends on How You Look at It (Score:3, Informative)
Regarding the photoelectric effect, Planck had already proposed the notion of discrete quanta of radiation a few years prior in order to get a consistent statistical-mechanical description of blackbody radiation that wasn't susceptible to the 'ultraviolet catastrophe'. Einstein ex
Re:Depends on How You Look at It (Score:2, Insightful)
Nope, that was already postulated by Newton. The laws of Newtonian mechanics are the same in all frames of reference and they are transformed by the Galilei-transformations. I guess this was also the drive for Lorentz to look for transformations which do the same on Maxwell's equations.
What Einstein managed was to bring these two contradictory theories into a consistent one, the Special Relativity.
</nit
Re:Depends on How You Look at It (Score:2, Informative)
I agree with the central message in your post. However, SR does include acceleration, jerk (the third derivative of position with time), and in principle all orders of positional change with time. You can also apply gravity as "just another force" in Newton's Second Law F=dp/dt, where F is the net force and dp/dt is the instantaneous rate of change of the momentum in time. Relativistically, p=gamma*m
Re:Maybe you can explain something to me... (Score:2)
Re:Maybe you can explain something to me... (Score:2)
Weird, eh? To oversimplify:
By the passenger's clocks, if they accelerate for a couple years, turn around then brake at 1G for a couple years to reach a nearby star, the trip took exactly as long as Newton predicted. From the point of view of people
Re:Maybe you can explain something to me... (Score:2)
Intertia is what makes it more difficult to accelerate. As you approach the speed of light, your mass increases m = m0/sqrt(1 - v^2/c^2) (relativistic mass); mass has inertia, so as your mass goes up, inertia goes up, and it takes more and more energy to overcome the inertia and accelerate the body. At v = c, m -
Re:Maybe you can explain something to me... (Score:2)
Re:Maybe you can explain something to me... (Score:3, Informative)
This is an oversimplification to the point of becoming myth - and the numbers don't even work out.
f = ma
The oversimplification is to suggest that if F produces less acceleration than expected, mass must be growing, but that's BS, because:
KE = (mv^2)/2
The relavistic correction for kinetic energy is the square of the correction for acceleration, *not* the same correction. Mass isn't changing at all, time is. Put Newton's law in the form Newton did, and this becomes
Re:Depends on How You Look at It (Score:2)
Look at it this way, you can easily measure the permittivity and permeability of free space in a normal sized lab without sophisticated equipment. You don't need to use incredibly large distances, nor worry about small times of measurement (ie
Re:Depends on How You Look at It (Score:3, Informative)
Don't get confused by the twin paradox and spaceships that have to accelerate. The twin paradox cheats on these issues as usually presented.
Re:Depends on How You Look at It (Score:2)
Re:Depends on How You Look at It (Score:2)
Re:Depends on How You Look at It (Score:2)
Re:Depends on How You Look at It (Score:2)
Re:Depends on How You Look at It (Score:2)
Re:Depends on How You Look at It (Score:2)
Re:Depends on How You Look at It (Score:2)
100 Years of Special Relativity (Score:4, Funny)
Re: 100 Years of Special Relativity (Score:2)
Please use those equations to calculate the path of this ball I'm going to throw deep. You'll understand what I mean. It just is plain neglibile in a general physics perspective.
But it does come into play while designing gigahertz circuits for sattelites or when calculating gravity pull of celestial bodies. Nothing an average man needs to know to calculate anything on earth (unless he works at CERN or something). Hence special .
Remember though. . . (Score:4, Informative)
My theory is just as credible as yours since it's only a theory and not a fact.
Ok, now that that diatribe is over, what's truly interesting is not that what Einstein proposed 100 years ago is still being studied and restudied, it's that one portion of it was recently confirmed. Frame dragging was only confirmed last year [universetoday.com].
Certainly other parts have been verified (relative time for example) but this portion, frame dragging, puts things in a whole new light. We're not just bodies in space. Instead, are bodies are changing the space around us!
Re:Remember though. . . (Score:2, Funny)
Re:Remember though. . . (Score:3, Informative)
Oh great, frame dragging (Score:3, Funny)
Re:Remember though. . . (Score:3, Informative)
Re:Remember though. . . (Score:3, Informative)
My theory is just as credible as yours since it's only a theory and not a fact.
It is an extremely well tested theory. For example particle accelerators would not work unless it were true.
Ok, now that that diatribe is over, what's truly interesting is not that what Einstein proposed 100 years ago is still being studied and restudied, it's that one portion of it was recen
Re:Remember though. . . (Score:2)
Yes, you are correct. I confused General and Special Relativity. My apologies. Good thing I don't have a geek card or it would be taken away for such an oversight.
Regardless, I still think it's cool that bodies in space can change space itself. Opens up interesting possibilities.
Re:Remember though. . . (Score:2)
I apologise - I mistook irony for the real thing
Re:Remember though. . . (Score:2)
Yeah, like gravity.
Re:Remember though. . . (Score:2)
Yes you silly wombat, the tiny demons are responsible for GENERAL relativity. Everyone knows that!
Re:Remember though. . . (Score:2)
Ah ha, ha ha. Another soul saved for the good Lord's work.
Re:Remember though. . . (Score:2)
Re:Remember though. . . (Score:2)
Re:Remember though. . . (Score:2)
And of course even QED ignores QCD and whatever quantum gravity turns out to be too.
100 Years of Special Relativity (Score:2)
Well, isn't that special.
[/Church Lady]
I Wonder What The Next Relativity Theory Will Be (Score:3, Insightful)
But it's already common knowledge that we don't have a GUT yet, and everything we do have seems very complex and overdone, much the same as it was before E=mc2
I can't help but wonder if someone will come along in the next decade or so and synthesize these more complex equations into another step forward for mankind. Who knows? Maybe the answer is something like "42"
Was Worf A Programmer? [whattofix.com]
Re:I Wonder What The Next Relativity Theory Will B (Score:3, Insightful)
> The guiness of Einstein was that he synthesized some more arcane work into some fairly simple equations, continuing to refine what we knew about the universe [...] I can't help but wonder if someone will come along in the next decade or so and synthesize these more complex equations into another step forward for mankind.
I'm sure more guiness [wikipedia.org] will help.
> But it's already common knowledge that we don't have a GUT yet, and everything we do have seems very complex and overdone, much the same as it w
Re:I Wonder What The Next Relativity Theory Will B (Score:2, Interesting)
The magic number (Score:2)
It's also possible this number may have
Black Mesa here we come (Score:2, Funny)
Lets hope we don't end up with a "Black Mesa" incident...
Re:Black Mesa here we come (Score:2)
Shotgun City 17!
Re:Black Mesa here we come (Score:2)
My view is that things are rather tedious at the moment. Physics has become mired in a swamp of obscure mathematics and possibly permanently untestable hypotheses (such as String theories). Any attempt to find out 'what is really going on' seems to have been forgotten in the race to publish indecipherable papers and come up with yet another 'how many dimensions this time?' idea. It is definitely Vroomfondel and Magikthise t
But it's ONLY a "theory" ... (Score:5, Funny)
Three cheers for the public domain. (Score:4, Insightful)
I am sorry, nothing deserves 120 years of copyright protection. I doubt almost anything needs even 28 years. I weep for those who will be looking back 100 years from now.
Re: Three cheers for the public domain. (Score:2)
> And just think -- under today's copyright laws of life+70, these papers would still be under copyright until 2025. Wikipedia is able to publish these today because copyright law was more sane a century ago.
> I am sorry, nothing deserves 120 years of copyright protection. I doubt almost anything needs even 28 years. I weep for those who will be looking back 100 years from now.
Nobody will be looking back, because there won't be anything for them to see without a fee.
Re:Three cheers for the public domain. (Score:2)
This is just one third of the World Year (Score:5, Insightful)
That was one hell of a year. Any one of those would have established his reputation, but all three, and in the same year!!
Re:This is just one third of the World Year (Score:3, Interesting)
Obligatory Family Guy Quote (Score:5, Funny)
Smith: I'd like to patent this. I call it "Smith's Theory of Relativity"
Einstein browses through Smith's work, nods approvingly and then kills Smith with the overhead window door
-everphilski-
The two postulates .. (Score:5, Informative)
.. the same laws of electrodynamics and optics will be valid for all frames of reference for which the equations of mechanics hold good. We will raise this conjecture (the purport of which will hereafter be called the "Principle of Relativity") to the status of a, postulate, and also introduce another postulate, which is only apparently irreconcilable with the former, namely, that light is always propagated in empty space with a definite velocity c which is independent of the state of motion of the emitting body. These two postulates suffice ..
The thing that needs explaining to me would be "frames of reference". A difference between two frames can be that they are in motion with respect to each other. For example, take a spaceship accelerating to half the speed of light, starting from our resting position. The 2nd postulate explains that the speed of light can be a constant velocity c, both with respect to the frame of the resting observer and the frame(view) of the spaceship. This leads to the question: if you shoot a light ray(velocity c=the speed of light) from the spaceship moving with half= 0.5 c, how come the light ray moves with 1.0 c from the view of both observers, not with 1.5 c from the resting observer?As Einstein states, he then proceeds to reconcile the two seemingly paradox postulates by formulating laws of electrodynamics that will work.
Re:The two postulates .. (Score:3, Insightful)
This is important because you can always tell by mechanical means if you are accelerating, but without a point of reference, you are unable to tell if you are moving at constant speed. (Gravity and circular motions are just accelerations)
Re:The two postulates .. (Score:2)
Are you sure?
What's the mechanical means to tell if I am floating in deep space or falling down a liftshaft (in a vacuum, obviously ;-).
J.
Re:The two postulates .. (Score:3, Informative)
Let me help: A frame of reference is anywhere from which you can observe anything. Really!
You sat in a chair is a frame of reference from which you observe the telly which is not moving much relative to you. You in a car moving across the surface of the earth is a FoR from which you observe roadsigns whipping past you at 70mph. You in a space ship is a FoR from which you observe stars and planets zooming past you at half the speed
Re:The two postulates .. (Score:3, Informative)
Maxwell's equations of electromagnetism predicted that an electromagnetic wave (such as light) would travel through space at a certain speed (c). This light is not travelling relative to any physical medium (such as the hypothetical 'aether'). The speed of light is
On a Related note (Score:2, Funny)
audio captures of lectures on special relativity (Score:2, Interesting)
I guess today is the day to finally listen to these...
http://www.teach12.com/ttc/EinsteinLectures.asp?a
Moving backwards (Score:4, Insightful)
Politicization of science (Score:2, Insightful)
What's more worrying is the increasingly extensive politicization of science (yes, it's always been political but it's getting even more so), the concomitant drop in the general education levels and the rise of anti-scie
Re:Moving backwards (Score:2)
Re:Moving backwards (Score:3, Insightful)
When you say we you use a pronoun that includes me. So that's me you're talking about there. I'm not discussing how dinosaurs attacked the ark. So you're offending me buddy. Watch what you're saying. You really mean "Today there's this crackpot talking about how dinsoaur's attacked the Ark...". And you see, when you phrase it correctly, it has nothing to do with Einstein but is just a statement about a crackpot. Crackpots existed in Einstein's time too.
Relativistic optics (Score:2)
Gravity Probe B (Score:4, Interesting)
Re:Gravity Probe B (Score:2)
Um... actually this is a result of general, not special, relativity. The centenial of that paper isn't for another decade or so.
The difference is that (in broad terms) general relativity concerns gravity and special relativity concerns objects moving at high speeds.
--Jeff
Sci-fi fans would do well to consider this... (Score:2, Interesting)
Re:Sci-fi fans would do well to consider this... (Score:3, Informative)
What are you talking about? Sci-Fi with integalactic travel almost never (never in my experience, but I'm sure there are some) has ships that go faster than light by just accelerating conventionally. They usually have some explanation for how they get around relativity (wormholes, shifting to diminsions with different rules etc).
It's rarely good science, but almost all Sci-Fi authors and fans do know about it.
galileo first stated relativity (Score:2, Interesting)
Galileo was trying to explain why its difficult to tell the earth is moving: when everything moves in unison its like relatively no motion at all. Thats why we dont have thousand mile winds at the equation, the soup doesnt pool to the east in its bowl, etc. The other image Galileo used was things and activities inside a moving ship.
Einstein amplified this
BBC radio stories to mark the centenary (Score:3, Informative)
Five specially commissioned short stories to mark the centenary of Einstein's discovery. Listen to them for next few days only here [bbc.co.uk].
Share and Enjoy!
Mod parent TROLL! (Score:2)
From TA:
How can I be involved?
You can organize an event in your community!
Parent post:
How can I be involved?
You can orgasmize an event in your community!
I know this is slashdot, but you sir, are abusing the system.
Anyway here's the coralcache link of the *REAL* article.
http://www.physics2005.org.nyud.net:8090/aboutwyp . html [nyud.net]
Re:In case of Slashdotting... (Score:3, Informative)
Re:Anus Misrabilis ? (Score:2)
It's just you. Really.
Re:einstein nuked japan (Score:2)
Re:Obvious oversimplification (Score:4, Funny)
Well said mate, well said!
See, there you have it!
Re:Albert didn't have instruments... (Score:2)
Re:5th paper (Score:3, Informative)
Re:Einstein's centenary - big in the UK (Score:5, Insightful)
Perhaps that is why they are hesitant. Brings up bad memories.
Re:Einstein's centenary - big in the UK (Score:2)
Various events for each country can be found he [wyp2005.org]
Re:Relativity has no basis to begin with (Score:2, Informative)
"This indicates that according to the Lorentz transformation, nothing can have the same speed relative to both K and K' unless it is a ray of light"
You then calmly assert that this is nonsense and claim certain mathematical assumptions are to blame. However, even a moment's thought about this indicates that this makes perfect sense - The two frames are in relative motion to one another, and thus for any object the observed velocity would be V = Vframe+Vobj