What is the Universe expanding into..

Do you think there was anything before the big bang?

  • I don't think there was anything before the Big Bang

    Votes: 56 12.5%
  • I think something existed before the Big Bang

    Votes: 200 44.7%
  • I don't think the big bang happened

    Votes: 54 12.1%
  • I think the universe is part of a mutiverse

    Votes: 201 45.0%

  • Total voters
    447
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I still haven't become a mathematician, but I think it would be the same impact as if one were stationary, and the other was travelling at C. In my opinion, because two C velocities can't sum. The total impact would be limited to the maximum of
1 x C.

I don't think it is the same thing. Particle accelerors are far more efficient with twin opposing colliding beams than with a single beam and a stationary target:

Colliding-beam storage rings

Although particles are sometimes accelerated in storage rings, the main purpose of these rings is to make possible energetic interactions between beams of particles moving in opposite directions.

When a moving object strikes an identical object that is at rest, at most half of the kinetic energy of the moving object is available to produce heat or to deform the objects; the remainder is accounted for by the motions of the objects after the encounter.

If, however, the two objects are in motion in opposite directions with equal speeds, then all the kinetic energy is available to produce heat or deformation at the instant of collision. If the objects stick together, the combination is at rest after the collision.

For particles with speeds close to that of light, the effect is accentuated. If a 400-GeV proton strikes a proton at rest, only 27.4 GeV are available for the interaction; the remainder produces motion of the particles.

On the other hand, if two 31.4-GeV protons collide, 62.3 GeV are available for the interaction (the collision is not quite “head-on”).

Particle accelerator - Colliding-beam storage rings | Britannica

Very good 11 minute explanation of velocity addition under relativity, and I got 12/13 with Discopete's hypothetical 2/3 lightspeed particles.

Relativistic Addition of Velocities - YouTube

The rocket velocities are relative to central observer on Earth.

Sorry to rant earlier. The constant changes of topic are frustrating me. I prefer to do one PROPERLY. :eek:
 
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I don't think it is the same thing. Particle accelerors are far more efficient with twin opposing colliding beams than with a single beam and a stationary target:



Particle accelerator - Colliding-beam storage rings | Britannica

Very good 11 minute explanation of velocity addition under relativity, and I got 12/13 with Discopete's hypothetical 2/3 lightspeed particles.

Relativistic Addition of Velocities - YouTube

The rocket velocities are relative to central observer on Earth.

Sorry to rant earlier. The constant changes of topic are frustrating me. I prefer to do one PROPERLY. :eek:
Ohh my Goodness! It took this guy over 11 minutes to make three simple statements! How many times did he repeat himself. Anybody take a count? Like talking to my wife...overandoverandoverandoverand... And he didn't even touch on travel in opposite directions!! Talk about puttin the kibosh on interesting :tilt:


:)
 
Particle accelerors are far more efficient with twin opposing colliding beams than with a single beam and a stationary target
By aiming a particle beam to collide head on with another beam, the 'centre-of-mass' energy is increased compared to aiming the beam at a fixed target.

It's complicated and beyond my descriptive abilities!: http://www.personal.soton.ac.uk/ab1u06/teaching/phys3002/course/13_accelerators_a.pdf

The total energy of a projectile particle plus the target particle depends on the reference frame.
The frame that is relevant is the centre-of-mass frame for which the projectile and target have equal and opposite momentum.
For relativistic particles, the centre-of-mass energy is considerably reduced.
 
I don't think it is the same thing. Particle accelerors are far more efficient with twin opposing colliding beams than with a single beam and a stationary target:



Particle accelerator - Colliding-beam storage rings | Britannica

Very good 11 minute explanation of velocity addition under relativity, and I got 12/13 with Discopete's hypothetical 2/3 lightspeed particles.

Relativistic Addition of Velocities - YouTube

The rocket velocities are relative to central observer on Earth.

Sorry to rant earlier. The constant changes of topic are frustrating me. I prefer to do one PROPERLY. :eek:

Particle beams approach the speed of light but don't reach C. Undetermined but less than 11 minutes.
 
But do the calculation, Discopete. It doesn't matter which direction the 2/3 lightspeed rockets are going. They approach other, cross, then move away. Nothing changes their relative speed Vab.

Relativistic Addition of Velocities - YouTube

Relativistic sum of velocities:

Vab = (Va - Vb) / (1 - (Va x Vb / c^2))

For Va = 2/3 and Vb = -2/3, Vab = 12/13.

I was surprised how big Vab was. But the maths does not lie.
 
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But do the calculation, Discopete. It doesn't matter which direction the 2/3 lightspeed rockets are going. They approach other, cross, then move away. Nothing changes their relative speed Vab.

Relativistic Addition of Velocities - YouTube

Relativistic sum of velocities:

Vab = (Va - Vb) / (1 - (Va x Vb / c^2))

For Va and Vb = 2/3, Vab = 12/13.

I was surprised how big Vab was. But the maths does not lie.
That makes no sense. This has to be a logical concept. Two cars passing in opposite directions are going to have a faster relative recession than if one just whizzed by a stalled one.
 
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Okay, I get that. However, would the impact of their collision be the same if one were stationary being hit by the other?

E=(mA+mB)c^2 in this case so the total mass involved is 20 tons.

c remains 298 million meters/sec

There is no difference in the impact energy other than the increased mass from mA + mB

In the LHC, the reason why particles are fired in opposition and then collide together is that you can, by doing this, get even closer the the limit of c. Maybe Galu can do the calc but it’s like instead of 99.999% of C it’s 99.9999999%. Since the required energies for the experiments are huge, this is a smart way to get closer to c than just firing a particle at a stationary target
 
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Since Steve was unable to quantify that for you, I decided to do the necessary calculation.

High energy particles arrive at the Earth's surface at a rate of 10,000 per square metre per second.

Since the average surface area of a man's body is 1.9 square metres, he would therefore intercept 19,000 particles per second.

Given that there are 86,400 seconds in a day, the daily total of particles intercepted would equal 1,641,600,000.

Thank you Galu
 
All back of a beermat stuff with me... :D

But interesting discoveries today.

I had a terrible time trying to solve the Galu Hypothesis on summing closing relativistic velocities of 2/3 lightspeed.

Tried E^2 = (p^2 x c^2) + m^2 x c^4, thought (p^2 x c^2) would reveal all.

and Kinetic Energy K = (Gamma - 1) m x c^2 where Gamma is the Lorentz square root factor.

Got about 4/5 Lightspeed each time. WRONG! 12/13 is right, as we know. :eek:

Did it with Galu's velocity transform and it came out better.

Centre of mass, the kinetic energy of the two particles is 0.6832 mc^2.

But from the different frame of one of the particles being stationary and the other one moving at 0.92 lightspeed the kinetic energy is 3.605 mc^2.

Bit weird you get different answers, but what reconciles it is the of the 3.605 mc^2, only a fraction is available to an impact, as we know from particle accelerators. The rest gets carried away in the debris.
 
Thank you Galu
Thank you, but my figure for the rate of arrival of high energy particles at the Earth's surface is probably way too high.

It depends on where on the Earth's surface we are, since the figure varies with latitude and altitude.

However, if our average man lives at a very high elevation and very near to the Earth's poles, the daily total I've calculated may not be too far out!

Whatever, it's safe to say that my figure of a man's daily dose of 1,641,600,000 particles is way too precise!
 
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E=(mA+mB)c^2 in this case so the total mass involved is 20 tons.

c remains 298 million meters/sec

There is no difference in the impact energy other than the increased mass from mA + mB

In the LHC, the reason why particles are fired in opposition and then collide together is that you can, by doing this, get even closer the the limit of c. Maybe Galu can do the calc but it’s like instead of 99.999% of C it’s 99.9999999%. Since the required energies for the experiments are huge, this is a smart way to get closer to c than just firing a particle at a stationary target
How does increased mass not result in increased impact energy?
 
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