OpenTube

Why Light Doesn’t Slow Down When You Chase It | Special Relativity Explained

Physics Investigated

34,780 views

Why is the speed of light in a vacuum always the same, even when you chase it? Follow the evidence from the ether hypothesis and the Michelson–Morley experiment to Einstein's special relativity—and discover why space and time must change instead.

This investigation explains the cosmic speed limit, spacetime, and the light cone: the boundary that governs which events can influence one another. Light can slow down in glass or water, and some patterns can appear faster than light; neither lets a usable signal cross empty space faster than c.

00:00 Why you can't catch light
01:17 What is light moving through?
01:56 Testing the ether wind
02:24 The Michelson–Morley experiment
03:12 What the missing clue really meant
04:15 Einstein's special relativity
05:00 Why space and time must change
06:19 The cosmic speed limit
07:09 The light cone and apparent exceptions
07:47 The bargain: constant light, different time
08:22 The next mystery: is there a universal present?

If you want to follow the next investigation, subscribe.

7 Comments

@aresjoel8720 2 days ago

I’m always hurt when people are confusing "Event" with "Perception of Event". Both "Event" and "Perception of Event" are themselves 2 separate events.

Only when we accurately understand how universe operates then we can draw conclusions from our observations "Perception" in these cases.

The problem science has today is deriving laws from "Perceptions" thinking that we are deriving them from "Event".

In simple terms "Event" is unic in the universe while "Perception/Observation" is not

@K3aker 9 hours ago

Opus 5.5 ftw
Are disclaimers not required?
It's quite well done btw, no shade

@helifynoe9930 5 days ago

Okay, let's say I have a light speed measuring instrument. It's big. It is compossed of a 299,792.458 km long ruler, and clocks are placed at opposite ends A and B. Thus one measures 1 second for light to go from one end to the other. So if your rulers spatial velocity is 260,000 km/s, then obviously the two clocks are now ticking at half the previous speed, the clock at the rear is ahead of the clock at the front by 0.866025 of a second, and the rulers new spatial length is now 1/2 of the previous 299,792.458 km length. All of the instruments changes that you are totally unaware of are what force you to still measure the speed of light as being the speed of light. But all of this would only happen if the ruler and you were in motion within space-time with the equal magnitude of motion of which photons of light themselves have. The only change you can make is change your direction of travel within space-time, meaning that all that you can change is your direction of travel within the 4D environment known as space-time, NOT your magnitude of motion.

@minetdbrogs9386 22 hours ago

Let guess something is aging relative to a particular time clock ?

@PhysicsInvestigated Creator 5 days ago

Which assumption is harder to give up: a universal clock, or the idea that you can gain on anything by moving faster? The next investigation asks whether the universe has a single present.

@PhysicsInvestigated Creator 2 days ago

I'll have to be honest here, after 12K views, which I was not expecting at all (thank you everyone so much), the thing I want the YouTube algorithm to notice is the lack of corrections in the comments. That's my #1 brag on this video, so I'm in hopes that YouTube will notice.