Why we can't reach the speed of light?

[patrickg]

Re: Why we can\'t reach the speed of light?

First, we hold this truth to be self evident, you can't reach the speed of light so what happens when you turn your headlights on at the SOL is not defined or possible. We can however theoretically approach arbitrarily close to the speed of light. Doing this and turning your headlights on would send out some extremely short wavelength E-M radiation way above that which we can see. This is as observed by the deer in your headlights. You however, could stick your hand out in front of the light and it would look perfectly normal to you. You would not see the deer because the reflected energy would be out of the envelope of wave lengths detected by your eyes.

Safety tip: Never out drive your headlights.

Worm holes indeed! Everybody wants to paraphrase script snippits from Deep Space Nine or was that Plan 9 From Outer Space?

If we lay out a closed road course 100 miles long per lap with starting and finish lines nearly colocated and some clever boy enters a soap box derby car (engineless) and as the race starts he pushes his entry by hand the 20 ft to the finish line and declares victory, he hasn't exceeded the speed of the other cars, he just took a short cut. Worm holes do not allow, permit, or make anything go faster than the speed of light, they just present a short cut of sorts. The other Formula racers in the previous example average (for the cars that aren't DNF) about 160 mph. No one would report the engineless soap box derby car as having EXCEEDED 160 mph. (He got there first, not having achieved a greater speed but by going a shorter distance. There is a very real difference to that.

Patrick

 

[patrickg]

Re: Why we can\'t reach the speed of light?

PS to wise guy:

Wise guy said:

Seriously, if I remember my physics correctly, the closer you get to the SOL, the energy
required to go 1/2 again as fast as you are traveling requires twice the energy you are
currently expending. Just like a prop driven aircraft is unable to break the speed of sound
because the faster you go the less effiencent the airfoil of the prop becomes.

I'm not too fond of the prop plane analogy and oh by the way some prop planes exceeded the speed of sound.

Sorry but I serouusly think someone may have told you wrong or confused you regarding approaching the speed of light. The energy required is a continuum. The curve is smooth, motonic, and differentiable but non-linear. Given the equations governing this, the energy required to accelerate something increases as velocity increases. The energy required to accelerate anything with mass (however tiny) to the SOL is infinite. That is, as the SOL is approached, the energy required for additional increases in speed are rapidly increasing (and run to infinity AT the SOL). That would be infinite energy required for each atomic particle in each atom in each molecule of the thing to be accelerated. Hard to get that much energy. Even with E=MC*C and converting all the mass in the universe to energy you wouldn't have enough energy to accelerate one lousy electron to the SOL. That is why worm holes,quantum tunnelling, etc is of so much interest.

Patrick

 

[patrickg]

Re: Why we can\'t reach the speed of light?

I was intentionally vague, stiring the pot to see what would bubble up. Thought it might be fun. Of course refs to SOL, unless otherwise specifically stated or implied in context, are in a vacuum in free space.

Ahh, Cherenkov radiation!

Bozons: A stream of particles ejected at high speed form a clown's ray gun.


Patrick

 

[patrickg]

Re: Why we can\'t reach the speed of light?

A friend of mine was told by his grand dad that the moon could be no further than about 200 miles from the earth because that was about as far as the human eye could see.

Of course exceeding about 60 mph would both disrupt your internal organs and suck all the wind out of your lungs and kill you.

Right up there with the Pres and CEO of IBM once predicting the world wide marketing potential for computers to be about 3 per year.(Or there abouts, been a while since I read aout that)

Patrick

 

[patrickg]

Re: Why we can\'t reach the speed of light?

Some of the simplest to describe effects of relatavistic physics that occur as speed increases are: (and these happen simultaneoulsy and continuously at an accelerated rate as speed is increased.)

The object under consideration shrinks along the axis of motion (pancake effect) thus occupying a smaller volume, increasing its density.

Its mass increases as velocity increases. And of course there is the bit about infinite energy required to get anything to the speed of light.

So, to recap: In the limit, as the object approaches the speed of light, it becomes two dimensional having no thickness or volume, it becomes infinite in mass and density, and more energy than exists or could be made from convertng all the univese (and all parallel universes) into energy is required to make this happen for even a single sub atomic particle. Gee, I wonder why a space ship can't do that?

Patrick

 

[patrickg]

Re: Why we can\'t reach the speed of light?

Yet another unwaranted assumption! Given that there is a god, why is it HE. If there is only one god, having a "sex" serves no purpose. How do we know that God can or does move around at all, much less all over the galaxy in a relative moment. Couldn't God just be? Don't mean to difficult, but has someone started up some new religion recently that involves cosmology in the doctrine. I thought those guys all drank the Koolaid.

Patrick

 

[Anonymous Poster]

Re: Why we can\'t reach the speed of light?

Patrick,

Your soap box theory is flawed because the boy did not actually cover the entire distance. Someone travelling from Earth to Mars via worm holes (generic term) would indeed cover the entire distance of the course arriving ahead of a conventional spaceship. Both went from a to b.

Did they go faster? Yes and no. They got there first but like in drag racing it is possible to go the same distance as the car in the other lane in less time with a lower top speed. You're probably right about my first post and the amount of energy required to break the SOL. I'm looking back quite a few years to physics class and the experts on TLC aren't always right.

Prop planes exceeding the SOS? I saw a 1934 WACO with a jet engine strapped underneath at an airshow last summer, maybe you mean that one? /w3tcompact/icons/smile.gif. Last I heard, Rarebear held the propdriven record and when adjusted to sealevel was still below the SOS. I would be interested in more on this topic.

Wise Guy

Iam not a scientist, but I did stay at a Holiday Inn last night.

 

[patrickg]

Re: Why we can\'t reach the speed of light?

Harv said: Not too ironic to discuss accelerating to the speed of light on a tractor forum.

Last Dec. I was having breakfast in a small ma-pa diner while waiting for bank to open in one of our large metropolitan areas nearby my place. That town is larger that thte closest one, it has over 500 residents. The next table over had 5 guys dressed in a mixture of western working (wester hats and boots) to farmer (bib overalls, ball caps). I expected to be treated to a discussion on beef futures, feed prices, whose cow had twins, and like that but instead one guy was holding forth extemporaneously about how when he gets deep into Stephen Hawkings latest book the calculus and tensors get in his way as his math skills are too rusty. He is a retired NASA eng, another fellow was a retired Hist prof recently retired from teaching at the U in Boston (author of many hist texts). Didn't get to meet the others but were probably not dumber than dirt and only knew hot to plow.

That was part of my motivation for stiring the pot with my speed of light gambit. Was curious what would come up.

Patrick

 

[GrantMO]

Re: Why we can\'t reach the speed of light?

Patrick,

If it is possible to travel faster than the speed of light, how would you measure it?

 

[patrickg]

Re: Why we can\'t reach the speed of light?

Grant asked: If it is possible to travel faster than the speed of light, how would you measure it?

Candidate answers selected from randomly chosen alternate realities from parallel universes:

1. You can't, so you don't.
2. Similar to traditional speed measurement. But since you get there before you leave, you interchange ending time and begining time in the formulas to avoid negative time in the formulas (a bear to dial with).
3. As the math so lucidly explicates, exceeding the SOL reverses the flow of time, so, had anyone done it they would have already traveled back in time and told us when in the future it was "going" to happen.
4. "Back to the Future" was a Government sponsored "training/propaganda film" to prepare the populace for the already in use time travel, some information of which was leaked via the "National Enquirer."
5. George W. is actually a simulacrum inhabited in a non symbiotic manner by a "grey". His body is being held in stasis pending the outcome of the next election which may be determined in the future by time travelling "greys" who aren't strange visitors from a distant planet but are strange visitors from a distant time and in fact are us, much later, here trying to fix things retroactively so to speak.
6. Irrespective of the perfection of the logic, if you do not accept a premise you cannot accept the conclusion. As faster than light travel is not possible, discussing or predicting "but what would happen if you could" is highly speculative at best.

SF invites us to suspend disbelief and boldy go where it is imposible to go. Thinking in those terms becomes so common place our familarity distorts our reason and we beginn to question science for not keeping up with fiction.

A simple example of trying to arrive at a quantifyable answer from an impossible situation:

Take a coin, flip it fairly and let it come to rest on a flat surface. Record the results, heads or tails (our coin has slightly worn edges and is incapable of landing on or being ballanced on edge) Now then, if when you flip it, it comes to a stable rest on a flat surface with both heads and tails showing record that event. Statistically we expect in a large number of tosses/flips we will get, within a small margin of variance, real close to 50% heads and 50% tails. What % of the time do you expect to simultaneously get both heads and tails?

Patrick