# what happens if the speed of light slows down

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. because you are traveling 3 years in space. What is an orbit? - Ellen McManis. But we asked some experts just to see how it would all go down. Within your car you observe no unusual effects. 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. From that point onward, everything proceeds according to normal physics. if I travel trough space with the speed of light or closer to it, does time slow down? 2) Light slows down when it passes through a medium (like water, glass, air, …). Light does NOT have mass, and gravity does not "slow everythinng down. How to slow down light until it stops In vacuum, light always travels at a constant speed of 299,792,458 metres per second. How does gravity work in space? If you haven't heard of or don't understand special relativity, don't worry too much about this note.) You also seem not to be sure of how either lightspeed or gravity is treated in general relativity. The waves slow down as they enter the shallow water which causes the wavelengths to shorten. When it comes to speed limits, the ultimate one set by the laws of physics themselves is the speed of light. If you’re able to travel near the speed of light, the effects are much more pronounced. We'll suppose it's a normal pitch, except in the instant the pitcher releases the ball, it magically accelerates to 0.9c. Basically, the closer you move to the speed of light, the slower time gets. 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. so that also means, 3 years had passed on earth. But … This change of direction is caused by a change in speed. For any speed u less than c this gives v = c so the speed of light is the same for you. 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". Not just the clock, mind you. 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. However, due to the nature of light, nothing could ever pass this speed limit. Everything in the ship must slow down. 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.) Get rid of those three errors, and it'll be a bit easier. There are only four forces- Gravitational, Electromagnetic, strong and weak nuclear force. So if a wave slows down, its wavelength will decrease. What travels in an orbit? I don’t know how changing the speed of light will affect the nuclear forces. 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? If you're talking about light traveling through empty space, then no, there is absolutely nothing we can do to slow it down. I mean if you are traveling 3 years with the speed of light and came back on earth. Scientists Slow Down Speed of Light. Let’s set aside the question of how we got the baseball moving that fast. wave speed = frequency × wavelength. 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##. Explaining refraction of light . The density. But if u = c the formula degenerates to zero divided by zero; a meaningless answer. 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. Read on 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. Going deeper (this is just speculation on my part) time would slow down, this is because of relativistic effects on time (time dilation). In a vacuum like space, the speed of light is just over 186,280 miles per second. Speed can be changed by increasing thrust to make a ship go faster, or retroburning or aerobraking to slow it down. Changing the speed of light would have profound effects on chemistry and the fundamental forces. Nothing can travel faster than this constant c, as denoted by physicists. The consequences can be horrible and disturbing! Light always has the same speed, the way it gets across a medium can vary very much. Change of speed causes change of direction. For what follows, the speed of light is now C = 100 mph (161 km/h for our Canadian or otherwise foreign readers). What causes an orbit to happen? But those changes are boring. After compensating for varying signal delays due to the changing distance between an observer and a moving clock (i.e. asked Jan 23 '13 at 22:24. chubbycantorset chubbycantorset. 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. If you want to know what happens when you are driving at very nearly the speed of light, an answer can be given. Add your answer and earn points. January 7, 2006, 12:38 PM • 2 min read. 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. The laser light also orders their random movement so they move in only one direction. 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. You would be surprised how many people have bluffed their way to a PhD without know this. so If I return back to earth, time would have traveled faster on earth? And since the acceleration cannot increase the speed of light, mustn't it slow down? What’s more interesting is the effects that special relativity would have on every day life. 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. If Earth were to suddenly spin out of control, you'd probably be too dead to worry about it. Moreover, general relatvity begins with invariant light speed as a postulate, but not on the metaphysical basis you propose. how many years would have passed? 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 effect of this can be shown using wave front diagrams, like the one below. What happens to the speed of light when it enters a glass prism? Slower speed is a misconception. For Trevor, the light is still bouncing at the same spot, so for him, time is functioning exactly the same way. 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). The first statement is the backbone of all of modern physics (relativity), and the second helps explain things like diffraction and rainbows. 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. The light waves that go through the glass don't actually slow down. In other words, the clock slows down. isn't it just 3 years??? 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. [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. By Tom Kirchofer. The index of refraction is determined by the electric and magnetic properties of the medium. Time does not appear to slow down. (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. 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. 1) The speed of light is an absolute. So, there is a drag on the wave, and it slows down. speed-of-light reflection. Qmechanic ♦ 140k 19 19 gold badges 318 318 silver badges 1658 1658 bronze badges. How do we put a spacecraft into orbit? How do scientists know what the path of an object in space will be? Even the minds of the people in the vehicle would have to reduce their movement through time! 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. share | cite | improve this question | follow | edited Jan 23 '13 at 23:30. 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