Science Brian Cox on Cern's baffling light-speed find

[Zarjazz]

Also, what happens if they are going the other way and crash into each other, would the impact speed would be close to 2x the speed of light?

Now you get to the whole point about relativity. This question has a different answer for each observer. Someone in a car would see the other car approaching at 0.994c (see my previous reply).

However someone on Earth looking at each car will see them each moving at 0.9c

 

[rynnor]

Interestingly I found out today that the phenomena of Neutrinos breaking the light speed barrier was first observed in 2007 during the Main Injector Neutrino Oscillation Search (MINOS) experiment in Minnesota.

They didnt make too much of it because they didnt have as good a fix on the two locations so their confidence level was much lower than the CERN experiment but they were planning to do a more accurate version in the next year or two.

 

[Tom]

Also, what happens if they are going the other way and crash into each other, would the impact speed would be close to 2x the speed of light?

It's a headache, but it's easier to deal with if you remember that at relativistic speeds, for the traveller, time slows to a crawl.

 

[Zarjazz]

for the traveller, time slows to a crawl.

No it doesn't. That's kind of the point. The traveller could carry a watch at near the speed of light and it would still tick once a second from their point of view. It's everything else that would appear to slow down.

The relativity mindfuck is that a stationary observer watching the traveller race by would say it was the travellers watch that was the one running slow.

 

[Tuthmes]

Even if the spaceship would move at the speed of light it still would take time (earth time) traveling around the world.

 

[Job]

I need help with this, there is a difference between 'looks' slow and 'is' slow.
You can mess with lightspeed all you like, but are the events themselves actually affected?

 

[Tuthmes]

What you need to get your mind around is:

You only observe things you can see (well not entirely true). For this you need (the) light to come/bounce off of it.

Secondly you need to loose the perception of time as you know it here on earth. Time isnt a constant, the lightspeed is. So time can vary. Just imagine how a fly looks at the world. Or a speed up of growing plants. It's still happening but the perception changes.

So in short, no the events themselves are not affected. It just looks different and you have less or more time to effect the event.

Atleast that's my understanding of it.

 

[Zarjazz]

I need help with this, there is a difference between 'looks' slow and 'is' slow.

Wrong. There's no such thing as is slow, only what can be measured relative to an observer.

You can mess with lightspeed all you like, but are the events themselves actually affected?

I'm not sure what events you are talking about here However I'm sure the answer is going to be no. Scientists sum this up by saying "the laws of physics are the same for all inertial observers" which basically means that anyone travelling at a constant speed and not under acceleration, be it 1mph or 99.99% the speed of light, located anywhere in the universe will all get the same answers, once adjusted for frame of reference, when measuring an event or experiment.

 

[TdC]

Job, you could look at it this way: the earth is orbiting the sun at a speed of about 30km/s. do you have any sense of speed when you stand outside? probably not, because you're going the same speed yourself so your motion relative to the earth is nil.

now, if you got in a car, and started driving at a speed of 30km/s you'd prolly have a hard time adjusting to the new speed relative once again to the earth and would perceive yourself to be travelling extremely quickly.

 

[Tuthmes]

Einstein's Relativity: Time Dilation - YouTube

Start at 3:51 or 6:41. The video is a bit gay though.

 

[Tom]

No it doesn't. That's kind of the point. The traveller could carry a watch at near the speed of light and it would still tick once a second from their point of view. It's everything else that would appear to slow down.

The relativity mindfuck is that a stationary observer watching the traveller race by would say it was the travellers watch that was the one running slow.

No, you missed my point entirely. For the traveller, time most certainly does slow down, since he can travel 20 light years, and to the observer appear to age by only a few days. The ticking watch is erroneous, since the traveller and the watch are moving at the same speed.

We're all moving through spacetime at the speed of light. Increase your speed through x, y or z, and you reduce it though time.

 

[Tuthmes]

No, you missed my point entirely. For the traveller, time most certainly does slow down, since he can travel 20 light years, and to the observer appear to age by only a few days. The ticking watch is erroneous, since the traveller and the watch are moving at the same speed.

We're all moving through spacetime at the speed of light. Increase your speed through x, y or z, and you reduce it though time.

For the travaller time doesnt slow down. For him (his point of view) the seconds still go by normally. Time isnt erroneous, its a variable. As to movie explains, if the lightspeed is the constant, then it's time that needs to change. The movie showed it with the 2 spaceships.

Perception wise I think you mean both are viewing eachother by tv or a screen or something?

 

[Tuthmes]

Nevermind the perception part, it's irrelevent. I'm thinkin erroneous myself. Even if you approach the speed of light the light it will still travel the same speed (not sure if i'm making sense here). So all the information comes at you exactly like it should.

Thank you, my brain is fried now.

 

[Lamp]

relativity for dummies:

http://www.oberlin.edu/physics/dstyer/Einstein/SRBook.pdf

 

[Tom]

For the travaller time doesnt slow down.

You are wrong. Simple as.

 

[Zarjazz]

You are wrong. Simple as.

Someone better tell the Physics community that Einstein was wrong.

"Special relativistic time dilation is often interpreted as time "slowing down" for the other (moving) clock. But that is only true from the physical point of view of the local observer. The point of view of the other observer will be that again the local clock (this time the other clock) is correct and it is the distant moving one that is slow."

 

[Tom]

I think we both understand exactly what it is we're saying. From my point of view, travelling on a light-speed vessel, if I return home and all my friends have died long ago, then time has slowed down for me.

Your quote actually supports my view, so well done there.

 

[Lamp]

"Special relativistic time dilation is often interpreted as time "slowing down" for the other (moving) clock. But that is only true from the physical point of view of the local observer. The point of view of the other observer will be that again the local clock (this time the other clock) is correct and it is the distant moving one that is slow."

He speaks the truth

 

[Job]

Ok if you accelerate away from an object towards the speed of light, you will see the objects movement slow down as you start to 'catch' the light up.
The theory of relativity dictates that 'time' for you also 'slows' down, I take that as meaning every physical interaction, even the spinning of electrons slow down compared to an object you 'leave' behind.
I'm putting things in commas, because all of those are human conceptions, why for instance does time 'slow' down for you, a person you leave behind is travelling just as fast away from you, what is the reference point? Staying still?
How do you 'stay still'?
Compared to someone who is moving on a universe scale?

 

[rynnor]

Someone better tell the Physics community that Einstein was wrong.

"Special relativistic time dilation is often interpreted as time "slowing down" for the other (moving) clock. But that is only true from the physical point of view of the local observer. The point of view of the other observer will be that again the local clock (this time the other clock) is correct and it is the distant moving one that is slow."

Unless Einstein has been accelerating at some fraction of the speed of light I figure its unlikely that he wrote that chunk of wikipedia you quoted above

Its also contradicted by the section further down the same article:

"Time dilation would make it possible for passengers in a fast-moving vehicle to travel further into the future while aging very little, in that their great speed slows down the rate of passage of on-board time."

 

[Zenith.UK]

There's a scene in "Young Einstein" that simplifies time dilation really well.

Einstein and Marie Curie are in Australia (don't ask!) and looking at a clock, she says "I wish this moment could last forever".

Albert Einstein: That's it! That's the theory of relativity! Light travels to us from the hands of the clock, to tell us the time. But, if we were to travel away from the clock at the speed of light...
Marie Curie: The hands of the clock would appear to have stopped!
Albert Einstein: Time would stand still! This moment *would* last forever.

 

[Tuthmes]

I think we both understand exactly what it is we're saying. From my point of view, travelling on a light-speed vessel, if I return home and all my friends have died long ago, then time has slowed down for me.

Or their time has speed up.

 

[CorNokZ]

Wish that I could ride my bike 1.5x the speed of light.. Then if I got pulled over at night and the cop asked me where my lights were I'd look back and say "here they come!"

 

[Job]

Yeah, but he was talking so slow, they arrived before he had time to finish.

So the Milky way is spinning at 600,000mph, so if you set of in a spaceship at 600,000
mph against the spin, YOU would be staying still and the rest of us would be accelerating away from you at 600,000mph, so YOU would get old and we would stay young.

Discalimer: This may not work.

 

[DaGaffer]

Yeah, but he was talking so slow, they arrived before he had time to finish.

So the Milky way is spinning at 600,000mph, so if you set of in a spaceship at 600,000
mph against the spin, YOU would be staying still and the rest of us would be accelerating away from you at 600,000mph, so YOU would get old and we would stay young.

Discalimer: This may not work.

Since 600,000MPH is actually less than 1% of c, no, it wouldn't work.

 

[Job]

You dont need to be at light speed, any speed works, the other problem would be you would be deorbiting yourself and the galactic core would start to pull you in

 

[DaGaffer]

You dont need to be at light speed, any speed works, the other problem would be you would be deorbiting yourself and the galactic core would start to pull you in

Time dilation effects are only really noticable (as in, all your friends got old and died) at high percentages of c.

 

[CorNokZ]

Time dilation effects are only really noticable (as in, all your friends got old and died) at high percentages of c.

The value of c has been proven wrong trololololol

 

[old.Tohtori]

Does this all babble mean that there are no ugly people, just variations on the time it takes to have sex with them, depending on the observer?

Also does this mean that the observer will affect the size of the penis?

How about the speed a girls knickers come off? Is it dependant on the light in the room, or indeed the knickers perception on the size of the penis?

 

[Zenith]

Been trying to catchup with this thread, and physics is not my strong suit, but surely, if you're travelling at light speed, and things seem to slow down, that must be due to your sensory organs not being able to perceive at such high speeds? Visual awareness is not entirely needed, but surely that must play in to what we perceive during those speeds?