Very interesting.

I am going to use this video on my defence the next time I'm pulled over for speeding.

"But officer, from MY perspective I was well under the limit."

upvote for being deep in the uncanny valley

That kind of confused me to be honest.

Comment hidden because you are ignoring dag.(show it anyway)

I thought it was a nice analogy and elegantly laid out. Though I think if we monkeys are not confused a little bit by this, we are not really getting it.

Downvote for the horrible presentation and confusing explanation... "easy" my ass. This could've been done a helluva lot better.

A 2-dimensional representation of a 4th-dimension concept. Brilliant! This monkey understands.

^ point was, that you look at your spacecar's progress as 1-dimensional, since it all depends on your frame of reference...

If you look at the spacecar's progress as moving along your imaginary X axis, then Y and Z are meaningless. Thus, a 4-dimensional problem becomes a 2-dimensional graph.

I liked the explanation, but maybe it confused me less than most because I have some physics experience, so these concepts weren't new to me.

yeah, not getting it. Gimme couple jesuses and I`ll start to comprehend.

So the lesson here is... if you want to stay relatively young, drive faster than everyone else.

Almost seems too simple.
- Everything (as far as we know now*) is traveling through SpaceTime at a fixed 186,000.
- An object with a Space velocity of 0 is still traveling through SpaceTime at 186,000, it's Time velocity = 186,000.
- An object with a Space velocity of 93,000 is still traveling through SpaceTime at 186,000, it's Time velocity = 93,000.
- And an object with a Space velocity of 186,000 is still traveling through SpaceTime at 186,000, it's Time velocity = 0.

*we don't know everything . 1000 years from now science may chuckle at our primitive belief that the speed of light was the theoretical maximum.

If I'm traveling at the speed of light while standing still, and light is traveling through space, but not time, what the fuck has that got to do with the dancing guy in the bear suit?

Keep in mind that when it talks about "moving through space" that the whole point of the theory of relativity is that it's all relative. There is no way to determine what is moving and what is at rest. There is no way to determine how fast you're moving through space. You can only say you're moving relative to some frame of reference.

LOL! He said that space has a NORTH.
And why do they have to use computer generated people instead of actual scientists?

When the Klingon Bird of Prey decloaked I was like, OMG!!!1!

But seriously, this does a great job at explaining the time / space relation. It still doesn't touch on one spot I've been trying to wrap my monkey brain around for some time.

Light travels at a set speed, nothing can travel faster then this speed. It's like a big universal speed limit. That should mean that if I'm traveling on a magical cosmic space train that's traveling in a straight line at.. lets say 500,000 mph, if I where to shine a flash light in the direction I'm traveling then the light emitting from that flashlight should travel (relative to me) at the speed of light minus 500,000 mph. Otherwise the light would be traveling faster then the speed of light to someone not onboard the magical cosmic space train.

This would also imply that there is a universal speed of 0. Which would mean we could measure our planet's speed through the universe to this speed of 0 by shining beams of light in various directions from our planet and measure how long each beam takes to reach certain distances (satellites positioned in front of each beam or something). After all our galaxy is moving through space, we're spinning in the arm of this galaxy, we're orbiting a sun.. all of these -should- factor in to how fast each of one is -actually- moving, right?

This big brainy friend of a friend told me once, no.. that's not how it works. And I suspect as much, unfortunately he wouldn't explain further. So I don't understand the workings of how there can be a set speed at which light travels and nothing can ever exceed this speed, when there's no specific speed of Zero to start accelerating from. Otherwise some things could very well be traveling faster then the speed of light relative to other things.

YOUR HEAD A SPLODE

if I where to shine a flash light in the direction I'm traveling then the light emitting from that flashlight should travel (relative to me) at the speed of light minus 500,000 mph. Otherwise the light would be traveling faster then the speed of light to someone not onboard the magical cosmic space


I think your wrong on this point, the speed of light is a constant. it will measure the same to all observers.

In regards to the quality of the video analogy, I've always found Dr. Quantum's physics videos extremely accessible and a model example of how to explain difficult science concepts.

http://www.videosift.com/video/Quantum-Physics-Double-Slit-Experiment-amazing-results
http://www.videosift.com/video/Dr-Quantum-Visits-a-2-Dimensional-World

Where can I get me one of them space cars?

Why'd they give virtual girl such a huge rack?

>> ^deathcow:
Why'd they give virtual girl such a huge rack?


To make it easier for male viewers to nod and say yes to whatever she explains. Would have worked out better with an live girl, however.

>> ^robdot:
if I where to shine a flash light in the direction I'm traveling then the light emitting from that flashlight should travel (relative to me) at the speed of light minus 500,000 mph. Otherwise the light would be traveling faster then the speed of light to someone not onboard the magical cosmic space

I think your wrong on this point, the speed of light is a constant. it will measure the same to all observers.


Then it -would- travel at speed of light minus the speed of the train to me, otherwise for someone "standing still" (whatever that is) the light would be traveling the speed of light plus the speed of the train.

I'm just gonna stop here before my HEAD ASPLODES.

uummm... no. the light would not travel the speed of light minus the speed of the train. the speed of light ALWAYS travels at the speed of light.regardless of source.

>> ^Memorare:
So the lesson here is... if you want to stay relatively young, drive faster than everyone else.

Worked like a charm for James Dean.

Let me put it this way. As I'm on the 500,000 MPH train, I ride through a star. At the same time I emerge from the star I turn the flashlight on. Is the light coming out of the flashlight moving forward at the same speed as the star's light outside? If so, then relative to me the light from the flashlight is moving at the speed of light minus 500,000 mph. The flashlight is traveling with me and emitting light as it does. If not, and the light is moving at the speed of light -from it's source-, then the light in the train is traveling 500,000 mph faster then the star's light outside.

Anyways, I've been directed to an interesting lecture on this, and apparently it's all more complicated then I could have hoped for. Yay.

>> ^Drax:
>> ^robdot:
if I where to shine a flash light in the direction I'm traveling then the light emitting from that flashlight should travel (relative to me) at the speed of light minus 500,000 mph. Otherwise the light would be traveling faster then the speed of light to someone not onboard the magical cosmic space
I think your wrong on this point, the speed of light is a constant. it will measure the same to all observers.

Then it -would- travel at speed of light minus the speed of the train to me, otherwise for someone "standing still" (whatever that is) the light would be traveling the speed of light plus the speed of the train.
I'm just gonna stop here before my HEAD ASPLODES.

This seems to be correct. Light travels at a constant speed through space. Unless your magic train is outside of space (and time) the light from your flashlight would travel at the speed of light, period. It is not affected by the speed of the emitter. The speed of light is a constant (yeah, refraction can make it SEEM like it changes, so can space expansion, but it's really a constant), and is not cumulative.
My question to math teachers was always..."If I'm going the speed of light in my chevy nova and I turn on my headlights, do they work?". Sadly, they never answered me, but the correct answer is "...kind of, define "work"." They would emit photons, but those photons would not go faster than the nova through space, and so they would not "light up" the space ahead of the car (as long as it traveled at the speed of light). My hypothesis is the photons would remain between the emitter and the reflector, and the "relative" speed of the car and light would be between 0 and twice the speed of light, but actual speed of each would remain the speed of light. There would not be a beam of light, but a point (or 2 points, one in front of or at the emitter, one in front of or at the reflector) where photons were traveling in the same direction, constantly gaining in "density".
A good question here might be, would there be a point where the photons reach a maximum "density" (where no more photons can occupy the same point in space time), and, if so, what happens when this point is reached?
Oh no! (head expands and pops!)

>> ^demon_ix:
>> ^deathcow:
Why'd they give virtual girl such a huge rack?

To make it easier for male viewers to nod and say yes to whatever she explains. Would have worked out better with an live girl, however.


Chyah! Good luck to them! They can't get a girl.

*ohsnapsickburndude*

All light is measured as traveling at the speed of light (300,000km/sec or 186,000miles/sec) by all observers. Even those traveling at or near c measure light to travel at c because their perception of time is altered by their velocity.

The misconception that if I'm traveling at .9c that if I shine a flashlight in front of me it will only appear to be traveling at .1c is because people forget to factor in how the passage of time (and space) changes for the observer at .9c. Remember, velocity is a measure of distance over time. Time passed for you is different from time passed for another observer at a different relative velocity. So the light particle travels 300,000km over one of your seconds while they measure it traveling 300,000km over one of their seconds. For each of you 1 second has passed and the 300,000km was traveled by the light particle leading to the same measurement for the speed of light by all observers.

Now it makes sense. Thank you.

But is space is expanding faster than the speed of light!

no,its not. but as some points move away from each other, the light from these points will never reach each other.