A speed beyond light question ^^

Actually, if Einstein's equations hold, your mass becomes infinite at the point you reach the speed of light. - I think there's 'divide by zero' error involved.

You should read Larry Niven's 'Man of steel, woman of kleenex' before quoting superman in a science thread :wink:

What interests me is moving into a different dimension.

Is it possible, in theory, that traveling beyond the speed of light allows this to happen?

If, as seems to be the case, space, time and obviously velocity are quantised then one can envisage a situation where one can travel at a speed of one 'velocity quanta' below lightspeed.
Then using the techniques of quantum tunneling one can see that it would be possible to move through the speed of light and find onesself at a velocity greater than that of lightspeed but never actually be at the speed of light.
Therefore it seems entirely possible that tunneling beyond the 'light barrier' is possible.

So far no such behaviour has been observed but clearly in the future it may be possible to test for such events experimentally.

gravity tunnel tubes exist

whowuddathunkit

Yeah.I know.Bit of an enigma aren't they?

This discussion so far is not scientific.

To have a reasonable discussion about this you need to understand that speed is relative-- that is speed has no meaning unless it is measured compared to something else.

Does anyone want to talk about the real science involved with velocity? You can't hope to jump to Einstein until you fully understand Galileo and Newton.

I know Galileo didn't like the look of the torture instruments and that Newton was stark,staring mad.

I'd certainly appreciate it if you filled it in a bit further.Full ahead.
There was a bloke in the pub the other night talking about the left-hand side of the Universe.It can't be harder than that to understand surely?

The first problem is the answer to the question "How fast are you moving?" The problem is that there is no way to answer this question unless you compare youself to something else.

This is a similar problem with the question "How far are you". If I asked you this question it doesn't make any sense. Better questions would be "How far are you from the North Pole?" or "How far are you from the Eiffel tower".

Unfortunately when we ask "How fast is that car going?" we all just assume that we mean "How fast is that car going compared to the Earth?"

If I asked "How fast is that car going compared to the Sun?", I would get a much different answer.

The problem is that if Sam and Beth are in spaceships, they can tell that the distance between them is increasing. But Sam may believe (with good reason) that he is motionless and that Beth is moving away from him. Beth at the same time may believe that Sam is moving away from her and that she is motionless. There is no scientific experiment in the world that can tell who is right.

The answer is that the question is wrong. It is not correct to say "How fast is Sam moving" without providing a reference point (which could be Beth) or could be another object (after all Chris says they are both moving).

The big confusion is that we live on the Earth which provides a very convincing reference point since in our experience the Earth doesn't move. Of course someone who is not from Earth would feel this is egocentric of us.

But it is a bad statement when you say "I am moving close to the speed of light...". You would have to say "I am moving close to the speed of light when compared to that fish, but then it would be just as correct to say that it was the fish who was moving at that great speed".

BTW This fact was articulated by Galileo. We haven't touched Einstein yet.

At the moment I feel stationary,more or less,but I know that I'm going at about 1000mph around the centre of the earth and at about 60,000 mph around the centre of the sun and at about 200,000 mph around the gravitational centre of the galaxy.

How fast is the galaxy going assuming the known Universe is stationary like I feel I am?

Could any of these various speeds cancel each other out like when you are staggering towards the rear compartment of a train with six cans of John Smith's Extra Smooth and the train is going the other way at 4mph due to it only having just pulled out and is only gradually accelerating because the grannies haven't practiced high G force training for such a long time.

Is it correct to say that we feel motionless due to gravity, despite the speed that the earth is rotating around the sun?

for example, if we were holding onto the poles of the merry-go rounds, we would be aware of the speed since the gravity is too low.

Honestly I do not know what I am talking about, hopefully it makes sense, and I would like to be enlightened on this topic with any information you can provide.

No, it is not correct to say this.

The fact is that speed doesn't exist... except when you compare yourself to something else. This means that you can't feel speed (there was a thought experiement I used when I taught Physics that is appropriate here which I will write when I have time).

You feel acceleration not speed. Acceleration is the change of speed or direction. What you feel when you go around a merry go round is acceleration (as you are changing direction).

The Earth, of course, is accelerating (i.e. spinning and revolving). You can measure this, but because of the scales involved you don't experience this acceleration in your daily life.

But you can't feel speed because if you measure yourself to the Earth (ignoring the acceleration) you are motionless. If you measure yourself compared to a comet that is passing by, you (and the Earth etc.) are moving pretty fast.

You never feel speed, you only feel acceleration which your mind over years of experience has convinced you is speed.

E wrote-



How fast is it accelerating?

yes

Acceleration is a vector meaning it has a value and a direction. However the higher the value, the bigger the effect of the acceleration so we will ignore the direction for right now.

The value of acceleration for a object in circular motion is (|v|^2/r) where |v| is the speed of the object (ignoring its direction, as read on a spedometer, and r is the radius of the circle around which it is travelling.

For the earth the radius is approximately our distance from the sun, or 93million miles.

You could find the speed (|v|) by dividing the circumferance of the earths orbit or 2 * pi * r, by the amount of time it takes the Earth to go around once-- which happens to be roughly 365 days.

To get a value that you can compare to other accelerations (i.e. gravity) you need to convert 365 days to seconds, and 93million miles to either feet or meters.

The acceleration of Earth's gravity is 9.8 meters/seconds^2 or 32 feet/seconds^2. Any acceleration that is much less than that, you will not feel. Any acceleration that is 10 times that or higher will kill you.

I did a quick search and didn't find an answer (I assume it is out there). If you do this calculation I suspect the answer will be quite low when compared to Earths gravity, simply because our distance from the sun (93 million miles) is quite large.

Let me give a thought experiment.

I kidnap you all and drug you. You wake up in a lead-lined steel box which I tell you is a train. The box is perfectly constructed so that no radio waves, sound, light or anything else enters the train from the outside. The train is on perfectly smooth tracks that will never cause any vibration or sound (which can't enter the train).

Now the good part. I will give you anything you want as far as scientific equipment. You can have steel balls, electronic equipment, nuclear reactors... whatever you can use anyway you want, as long as you don't penetrate or damage the walss of the train.

The problem is this....

How can you tell how fast the train is moving?
How can you tell what direction the train is moving?
How can you tell IF the train is moving?

If you were to place the metal balls on the floor of the box, wouldn't they move in the opposite direction the train is travelling in? Or would they remain motionless?

How refreshing crayon, well said. Others please note.

No. If the train were not accelerating the balls would not appear to be moving.

You know this is true if you have ever ridden in an airplane (or even a car) that is moving (compared to the earth) in a straight line without slowing down or speeding up.

I have ridden in an airplane going more than 300 mph. I can put things on the tray in front of me and to me they appear to be motionless. Pf course when the plane is accelerating (speeding up to take off for example), anything on my tray gets "pushed" backwards onto my lap. But when the plane is in steady level flight, any objects appear to be motionless.

So putting metal balls (or anything else) on the floor will give you no clue about the motion of the box.

I must say,at this point,that I wasn't trying to unleash all this comical banter.

What I was wondering,scientifically, was that if the earth was accelerating,as E said it was,how long will it take before centrifugal forces chuck us all off into orbit or even further.Will fatties be "selected in" by dint of them lasting longest and,logically,should I try getting fat by gorging on all my favourite gobdribblers.