because you are traveling 3 years in space. How do scientists know what the path of an object in space will be? Read on What’s more interesting is the effects that special relativity would have on every day life. Within your car you observe no unusual effects. If Earth were to suddenly spin out of control, you'd probably be too dead to worry about it. It does slow down, and it has been proved in several experiments: for example, atomic particles traveling near the speed of light decay slower than expected when observed by a stationary observer. I mean if you are traveling 3 years with the speed of light and came back on earth. Change of speed causes change of direction. Light always has the same speed, the way it gets across a medium can vary very much. how many years would have passed? Slower speed is a misconception. - Ellen McManis. The laser light also orders their random movement so they move in only one direction. The light waves that go through the glass don't actually slow down. Nothing can travel faster than this constant c, as denoted by physicists. When light enters a transparent medium, it becomes a phonon - it's no longer a photon travelling through a vacuum at the speed of light, it's a wave being propagated through a medium. asked Jan 23 '13 at 22:24. chubbycantorset chubbycantorset. By Tom Kirchofer. In a vacuum like space, the speed of light is just over 186,280 miles per second. However, due to the nature of light, nothing could ever pass this speed limit. And since the acceleration cannot increase the speed of light, mustn't it slow down? I don’t know how changing the speed of light will affect the nuclear forces. You also seem not to be sure of how either lightspeed or gravity is treated in general relativity. This change of direction is caused by a change in speed. The index of refraction is determined by the electric and magnetic properties of the medium. In other words, the clock slows down. Going deeper (this is just speculation on my part) time would slow down, this is because of relativistic effects on time (time dilation). How do we put a spacecraft into orbit? Light refracts whenever it travels at an angle into a substance with a different refractive index (optical density). (In fact, special relativity says that even if we run away from a light wave really really fast, it will still be coming towards us with the same speed. If you were to get into a spaceship that traveled very quickly away from Earth, time inside the ship would slow down in comparison to that on Earth. 2) Light slows down when it passes through a medium (like water, glass, air, …). Explaining refraction of light . For any speed u less than c this gives v = c so the speed of light is the same for you. If you’re able to travel near the speed of light, the effects are much more pronounced. As the atoms absorb particles of light (photons), they slow down. What would happen if you tried to hit a baseball pitched at 90% the speed of light? Even the minds of the people in the vehicle would have to reduce their movement through time! Get rid of those three errors, and it'll be a bit easier. But if u = c the formula degenerates to zero divided by zero; a meaningless answer. Time dilation is a difference in the elapsed time as measured by two clocks due to a relative velocity between them or to a difference in gravitational potential between their locations. But those changes are boring. the flow of time doesn't change very much), but at speeds over about 75% of the speed of light the effect of time dilation is quite dramatic. so If I return back to earth, time would have traveled faster on earth? so that also means, 3 years had passed on earth. It does slow down (well - that's not really what happens at any speed, but it's a close enough description for the purposes of this question). Time does not appear to slow down. Everything in the ship must slow down. For what follows, the speed of light is now C = 100 mph (161 km/h for our Canadian or otherwise foreign readers). Relativistic effects are related to the speed of light in vacuum (c), so you won't see them more easily merely by slowing light down in a medium. The effect of this can be shown using wave front diagrams, like the one below. Light does NOT have mass, and gravity does not "slow everythinng down. Changing the speed of light would have profound effects on chemistry and the fundamental forces. share | cite | improve this question | follow | edited Jan 23 '13 at 23:30. Einstein imagined what would happen if the tramcar were to travel at the speed of light.With the grand clock tower in his sight, Einstein realized that if he were traveling at 186,000 miles per second, the clock’s hands, which already moved so solemnly, would now appear to completely freeze. So, there is a drag on the wave, and it slows down. The slow light experiments are mentioned in Dave Eggers's novel You Shall Know Our Velocity (2002), in which the speed of light is described as a "Sunday crawl". After compensating for varying signal delays due to the changing distance between an observer and a moving clock (i.e. 1) The speed of light is an absolute. Scientists Slow Down Speed of Light. But … The consequences can be horrible and disturbing! If you want to know what happens when you are driving at very nearly the speed of light, an answer can be given. What is an orbit? Not just the clock, mind you. What happens to the speed of light when it enters a glass prism? The first statement is the backbone of all of modern physics (relativity), and the second helps explain things like diffraction and rainbows. How to slow down light until it stops In vacuum, light always travels at a constant speed of 299,792,458 metres per second. Speed can be changed by increasing thrust to make a ship go faster, or retroburning or aerobraking to slow it down. So if a wave slows down, its wavelength will decrease. It is possible for matter to travel faster than light in a medium, though less than c: when charged particles do so, they produce what is known as Cherenkov radiation (kind of a "sonic boom for light"). The waves slow down as they enter the shallow water which causes the wavelengths to shorten. From that point onward, everything proceeds according to normal physics. If you and I synchronise our watches and then you walk to the other side of the room and back at speed ##v## then my watch will show elapsed time ##T## and yours will show elapsed time ##\sqrt{1-\frac{v^2}{c^2}}T##. When the atoms are slowed to a modest 100 miles an hour or so, the experimenters load the atoms into what they call “optical molasses,” a web of more laser beams. [URGENT ANSWER NOW, IM IN A HURRY] it speeds up it slows down it curves through the glass it bends when entering the glass it separates into colors 1 See answer beckhamschooling is waiting for your help. January 7, 2006, 12:38 PM • 2 min read. We'll suppose it's a normal pitch, except in the instant the pitcher releases the ball, it magically accelerates to 0.9c. When light enters a denser medium (like from air to glass) the speed and wavelength of the light wave decrease while the frequency stays the same. How much light slows down depends on the new medium's index of refraction, n. (The speed of light in a medium with index n is c/n.) speed-of-light reflection. if I travel trough space with the speed of light or closer to it, does time slow down? Let’s set aside the question of how we got the baseball moving that fast. The density. wave speed = frequency × wavelength. Moreover, general relatvity begins with invariant light speed as a postulate, but not on the metaphysical basis you propose. How does gravity work in space? The photons always travel at the same speed, only when they enter a denser medium, it takes longer for the photon to get to the other side because it encounters matter which deflects it's path from straight to inclined. On Discworld , where Terry Pratchett 's novel series takes place, light travels only a few hundred miles per hour due to Discworld's "embarrassingly strong" magic field. We can see from the graph that at “low” speeds there is only a small change in time dilation (i.e. Physicists have just found a way to slow light down without touching or intercepting it, simply by making it 'twist' as it moves through space.. That means they were able to make beams of light take longer to get from point A to point B, a skill that will be incredibly useful when it comes to controlling the next-generation of optical computers and telecommunication systems. What travels in an orbit? When it comes to speed limits, the ultimate one set by the laws of physics themselves is the speed of light. Qmechanic ♦ 140k 19 19 gold badges 318 318 silver badges 1658 1658 bronze badges. isn't it just 3 years??? If you haven't heard of or don't understand special relativity, don't worry too much about this note.) What causes an orbit to happen? Basically, the closer you move to the speed of light, the slower time gets. The effect is only apparent and applies to the speed of light 'in the material' as opposed to the speed of light 'in vacuum' where light ALWAYS travels at the speed of light c. The reason you treat the light as if it did slow down is an effect of the wave nature of light. For Trevor, the light is still bouncing at the same spot, so for him, time is functioning exactly the same way. If you're talking about light traveling through empty space, then no, there is absolutely nothing we can do to slow it down. You would be surprised how many people have bluffed their way to a PhD without know this. Scientists slow down the speed of light travelling in free space Date: January 23, 2015 Source: University of Glasgow Summary: Scientists have managed to slow photons in free space for the first time. Add your answer and earn points. But we asked some experts just to see how it would all go down. There are only four forces- Gravitational, Electromagnetic, strong and weak nuclear force. Relatvity begins with invariant light speed as a postulate, but not on the metaphysical basis you propose when comes... ♦ 140k 19 19 gold badges 318 318 silver badges 1658 1658 bronze.. 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