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Excursions at the Speed of Light
D4C5CE writes "S/F fans can finally find out what you really get to see at relativistic velocity, and tourists are one step closer to "doing Europe in a day" in these amazing Space Time Travel simulations of the Theoretical Astrophysics & Computational Physics department at the Institute for Astronomy and Astrophysics Tübingen. They put you in a driver's seat that both Armstrong the Astronaut and Armstrong the Cyclist would equally enjoy, in simulators built to ride a bike at the speed of light."
I'm presently ingrossed in Brian Greene's new book called "The Fabric of the Cosmos" and does a wonderful job at creating lively understandable analogies while sticking to alot of interesting science. He covers the history and philospophy of how problems involving realtivity, time, and space have evolved - stronly reccomend it...
If religous zealots don't believe in Evolution, then why are they so worried about bird flu?
G-force is caused by acceleration. Assuming you accelerate slowly enough, you can get up to $VERY_FAST without dying.
G force is dependent on acceleration, not velocity. If one were to be accelerated too quickly to the speed of light, you would likely not survive. But if one were to accelerate to the speed of light under livable circumstances, it would not rip your skin off. Once traveling at the speed of light, you will feel just like you feel when traveling in an airplane
Lightspeed is a simulator for velocities at c and below. Screenshots are available.
Illegal? Samir, This is America.
It's a little sad that most people still don't understand the difference between speed and acceleration. When I first read about the Scientific Revolution as a kid, the writer spent a lot of time sneering at medieval scholars who stubornly stuck to Aristotle's physics despite all the experimental evidence showing that it was wrong. But as far as most people are concerned (including the script writers on Star Trek) Aristotle has never been debunked.
I have seem something similar to this before. Check out:
http://www.anu.edu.au/Physics/Searle/
and
http://www.anu.edu.au/Physics/Savage/TEE/
Look, I've been through Tübingen at the speed of light, and it doesn't look anything like that!
eleven plus two / twelve plus one
All this does is attempt to simulate the visual distortion that one would perceive when traveling that fast. The videos look like you could be going 100 mph or whatever in terms of speed, but the distortion of the buildings seems to be what they're trying to get across here. The idea that you could have a long enough street lined with similar enough buildings to even perceive this distortion is beyond fantastical, so there doesn't seem to be a whole lot of point to this other than illustrating the notion that there is visual distortion. But I imagine what you would actually see would be much more of a blur.
Stand still, and let the rest of the universe move.
That's wrong...Time would pass normally for you. You would think at a slower speed (the same speed you're moving) so you wouldn't notice a difference. When you got off the bike, however, much more time would have passed for everyone else than you.
All this is, of course, assuming Einstein was right (and I think some experiment somewhere proved these effects to be correct)
or maybe that's brown bike shorts.
eww.
Thats one long block! The movie is 3 or 4 seconds long, so that is a 1,200,000 km street block.
There is quite a bit of very convencing physical evidence for both special and general relativity. Here's the first google item returned, but there's lots more out there to read. http://math.ucr.edu/home/baez/physics/Relativity/S R/experiments.html
We must proceed with caution by ceasing these speed-of-light simulations. The Chinese would surely use them to advance their space-weaponization program.
Why does this troll keep showing up? The Chinese don't have the resources to compete with the US. They've attempted manned space travel several times (even outright copying the Dynasoar design) and every time have had to cut it because of the cost. For now, I wouldn't worry too much about the Chinese one-upping the US on their own technology. Start worrying when they launch an Orion (not bloody likely).
Note that the Chinese space program is completely under the auspices of the Chinese department of war. By contrast, in the USA, NASA is an entirely civilian effort.
This is a GOOD thing. Remember what happened when the space program was under the United States department of war? (Specifically the Air Force?) That's right, some good engineering was done, but we didn't GET anywhere. It wasn't until NASA was formed that the US actually got into the race.
Javascript + Nintendo DSi = DSiCade
This is what I see when I sprint to an all you can eat buffet after someone else has offered to pay. I have been called many things, but late for dinner is not one of them.
They're simulating the *visual* effect which is much different than just the Lorentz transformation because of the differing light travel times from various parts of the object to your eyes. For example, a body actually appears *rotated* instead of just Lorentz contracted.
I prefer Ludicrous speed!
Even those who arrange and design shrubberies are under considerable economic stress at this period in history.
It's in the this explanation. There's a diagram at the bottom which explains it much better than I can in words.
I showed my wife the videos cause they were cool, but she got all misty-eyed about seeing Tubingen again, so I'm in for a long night of hearing about how much fun she had at university there. Sigh. Why can't more people appreciate the value of astrophysics for astrophysics' sake?
The world's only surviving livewriter.
Very cool project - the screenshots posted by the parent comment show nicely that the Tübingen Project forgot to adjust the colors - due to the Doppler effect, colors change dramatically.
Under capitalism man exploits man. Under communism it's the other way around.
Sure.
See light travels at the speed of light. You cant travel faster, or even AT the speed of light.
But if youre zipping by an object that emits light, and its light doesnt travel in the same direction as you, its speed component in that direction is also slower than the speed of light, and you can catch up and see the object after you're past it.
Lets try that again.
Imagine youre on a bike, zipping past a lamppost. The light the lamppost emits travels in all directions. Now take the photos that are emitted in the same direction youre going, at the same time that youre just crossing the lamppost... now youre travelling parallel to that photon, although it beats you in speed.
However, if the lamppost was say 10m away from you when you zipped past, the photon you'd see is the photon the lamp emits not in the same direction youre travelling, but slightly towards you. If youre travelling north, the photon is travelling northwest, towards you. After youve crossed the lamppost, some distance later, the photon reaches you, because it had to travel a bigger distance, going in your travel direction (north) as well as towards you (west), and we all know the hypotenuse is longer than the base or height.If you travelled faster than the photon's north speed component, you'll see greater than 180 degrees around you... but never 360.
"Give orange me give eat orange me eat orange give me eat orange give me you." -Nim Chimpsky
They are missing the blueshift you would encounter at that speed. However I guess they couldn't be accurate because wouldn't the frequency would shift to far above the ultraviolet quite quickly?
History will be kind to me, for I intend to write it - Sir Winston Churchill
There should, I think, have been at least a nod given to George Gamow whose 1947 book, "Mr. Tompkins in Wonderland," attempted to explain relativity and quantum mechanics by putting Mr. Tompkins into situations like this. If I remember correctly, one of the episodes literally did involve his riding a bicycle in a Wonderland in which c was something like twenty miles an hour.
"How to Do Nothing," kids activities, back in print!
"They put you in a driver's seat that both Armstrong the Astronaut and Armstrong the Cyclist would equally enjoy"
But what about Armstrong the overly stretchy action figure?
Everyone is entitled to their own opinion. It's just that yours is stupid.
300000000/50 = 6000000 seconds, or about 70 days.
Deceleration would require the same amount of time. So the Tübingen experience would be a 140-day-not-very-pleasent-5-G bike ride :)
My UID is prime. Hah!
At forward viewing angles, yes, the images would be blue-shifted, but this doesn't mean everything goes dark. Visible becomes UV, and infrared becomes visible. But this is angle-dependent. Light arriving from behind you is actually red-shifted.
And yes, pushing several hundred watts per square meter of visible light into the UV range would result in a terrible sunburn.
But the point is that while you are going the speed of light, while time appears normal to you, you will have traveled an infinite distance in that first instant of time in your reference frame.
Which leads to the observation that you could never stop going the speed of light, because when you decide to hit the brakes X seconds later, you would have traveled an infinite distance. Where would you end up? (Never mind the problem of having to dissipate infinite energy)
Well, at the speed of light... yes, things going at the speed of light experience nothing that can be called the progression of time.
But matter can't travel that fast, only things without mass. So, there is the interesting question of what you have that you would call a "bike" or "you".
Physics does not break at the speed of light, but intuitive physics is dead. Relativity is a strain on it at any high speed but just forget lightspeed.
(As I always do when this topic comes up, if you want a crack at understanding this stuff for real, try Reflections on Relativity, free online.)
Ha, that's easy for a level 7 magic user to say! Some people simply don't have the high INT scores to understand the difference between speed and acceleration. That's why they're so BAD at using a bow and arrow, or even a sling (even level 1 wizards can use a sling hahaa). Anyway, after slaying this sweet dragon last week, I found like a million +2 INT hats. Maybe I should sell them and get rich then everyone would know the difference between acceleration and speed and you wouldn't have a reason to be so sad.
Btw, that was a hilarious email forward you sent me about "10 ways warriors are dumb". You should add a new one to the list 11) Warriors can't even name five flaws in Aristotle's physics!! haha So is your mom still mad or can we play at your house again on Tuesday?
Not bad, for a bot. Is your source code available?
Yes, a person moving faster than another is affected by time differently. Time Dilation is one of the components of Einstein's theory of special relativity.
"When I grow up, I want to be a weirdo"
Those curved buildings are kinda cool, but how long would those buildings even be in your field of vision if you were blasting past them at the speed of light?
First of all, it's near lightspeed.
More importantly, they simulated light moving at 30km/h rather than 300km/s. Fortunately this had no effect on the real speed of light, so you're free to continue driving at highway speeds. Good thing too, because it would add a whole new dimension to traffic violations.
"Your honor, I literally couldn't see him until after we collided."
"$500 fine for exceeding the speed of light."
"Your honor, I didn't realize.. I thought I was just drunk!"
https://www.eff.org/https-everywhere
No... Constant velocity = no acceleration. Constant high speed in a circle (such as in orbit)= lots of acceleration.
I'll never make that mistake again, reading the experts' opinions. - Feynman
That's Newtonian. The relativistic acceleration equations are different. See this FAQ for the correct equations, which will tell you how long (in either proper or inertial time) it would take to reach a given speed, as measured by an inertial observer initially at rest with respect to the body -- with some calculations for 1 g acceleration.
(For instance, to reach 0.77c requires 1 year of subjective time or 1.19 years of objective time; for 0.97c, it's 2 years subjective, 3.75 years objective; for 0.99999999996c it's 12 years subjective, 113,243 years objective.)
C'mon, surely someone else remembers the episode of Carl Sagan's series "Cosmos" where they did the relativistic motor scooter trick? In a small town in Italy, where the speed of light is only 40 km/hr (strictly enforced!) a young man leaves on a tour of the city at relativistic speeds, leaving his friend and younger brother behind. Sagan describes the effects of blue- and red-shifting, the contraction of the cyclist's length, and the dilation of time. It ends with the young man returning to the place he started, just a few minutes (in his frame of reference) after he left. Sadly, he finds all his friends gone, and only his once-younger brother, now an old man, still waiting for him.
I don't know why, but the bittersweet reunion of the two brothers, as well as the story of the late Wolf Vishniac in the "Blues for a Red Planet" episode, both make me cry.
Velocity is a vector quantity, basically speed times a direction vector. If you turn, it takes a force to push you in the new direction. Since F=MA, that means that you are being accelerated. If you were to drive a car in a clockwise circle at a speed of 100 MPH, it would be constantly accelerated to the right, but its speed would remain 100 MPH. However the net velocity would be zero, as the net spatial displacement would be zero (at least every time you come back to the start point.)
And orbiting bodies continually lost speed? What kind of troll weed are you putting in your pipe?
I'll never make that mistake again, reading the experts' opinions. - Feynman
What you're talking about (the slowing down of light in glass, etc.) is the effect of light hitting a molecule of something, being absorbed by it, and then being reemitted out the other end.
Light's speed is a constant, c. It's the speed of absorbtion and reemission that changes it's apparent speed through substances.
I [may] disapprove of what you say, but I will defend to the death your right to say it.
Slow Light is around 1.6 Kms per hour
Quidquid latine dictum sit, altum videtur