Physics in the Philip Imbrogno 9/7/08 Episode

[Particle Physicist]

I've listen to the show a great deal and enjoy it greatly however, I have to take exception to the comment in the last show that people behind M-Theory and [Super]String theory "are not considered to be the main stream of the physics world". This is not the case. Further, it was stated that Professor Greene and Professor Kaku are considered "as much entertainers as they are scientists". Wow, that is a strong statement David. You also started off mentioning the field of "experimental physics" then went on to state that two theoretical physicists are "on the fringe" of this field

The correct term here would be "Popularizer of Science". They have made very valuable contributions to theoretical physics and have the rare skill of being able to do this as well as get complex concepts across to the layman. Other notable scientists with this skill have been Carl Segan and the great physicist Richard Feynman.

I come across a lot of physics woowoo in regards to the Paranormal, a lot of it stems back to lack of knowledge, for example in the show it was implied that the ideas of String theory are bleeding edge however the theory was initially proposed in 1969; it is almost 40 years old. Quantum Theory comes up a great deal in the paranormal to explain everything, strange as I would confidently state that this is the most well tested theory in the history of science. This can be traced back to the late 1800 century.

Anyway, thought I would mention it as you seem to get frustrated when people state known falsehoods.

Regarding other aspects of Physics and the paranormal, I am tired of hearing about how people claim that the ETH is invalid as the universe is too big and it would take many years, even at the speed of light, to travel from the even the closest star system to Earth. Special Relativity tells us that this time is relative and for people on board the ship, at the speed of light, no time would pass at all. Just to be clear, you could travel from Earth to the Andromeda Galaxy (whch is 2.5 million light years away) and not age a second if you traveled at the speed of light. Of course if you went and came back to earth 5 Million years would have passed here and in effect you have traveled in to the future. Not that the ETH is valid, I have no idea but distance doesn't invalidate it especially if beings had dispensed with using a planet and were purely space based.

The scientific method as mentioned on the show; as a scientist (who has had some experiences, hence my interest in the field) I would say it would be very difficult to apply to UFO sightings as these are not something that tends to be repeatable. Yes it can be applied to encounters of the 2nd kind but the majority of cases involve encounters of the first kind, I'm not sure how the scientific method could be applied there. Particle physics could be important though, if the Higgs is found by the LHC, this could help point us in the right direction to make our own vehicles that would at least perform like UFOs are said to; it is theorized that the higgs boson interacts with the Higgs field to give particles mass (a boson is a force carrier). Block this interaction and you could perform 90 degree turns at high speed or accelerate quickly without any G-force effects.

Finally, I'd like to see you cover crop circles, some are obvious fakes and I'm sure many are just very well done elaborate fakes however, some of the huge intricate formations raise a few more questions and at least there is some physical evidence. This is not a field I know well (the paranormal) and to be honest I suspect it is a field of inquiry that if taken too seriously would lead to frustration due to the lack of progress but I enjoy the show greatly and I wish to thank you for your hard work on it.

 

[Drew UK]

Special Relativity tells us that this time is relative and for people on board the ship, at the speed of light, no time would pass at all. Just to be clear, you could travel from Earth to the Andromeda Galaxy (whch is 2.5 million light years away) and not age a second if you traveled at the speed of light.

I don't get it - you mean light does not age a second.
I find it difficult to intuitively get my head round these theories.
I would prefer time to be constant rather than the velocity of light which is a component of distance/time.
Why do we calibrate time against light anyway? Isn't it like saying the mass of 1g of water is fixed which is a component of 1cm (length)x1cm(depth)x1cm(height) vol. of water?

Until I get more beautiful equations and explanations I am sticking with Newton.

 

[Drew UK]

p.s When I first sat my quantum physics/chemistry modules I failed badly. But, on the resit I passed with flying colours. The trick was not really understanding it but making all the equations fit together -it was a bit like sudoku.
If anyone can shed the light on the "light velocity bit" it would be appreciated - I have been waiting a few light years.

 

[Gareth]

Drew I think its to do with the theory that time slows down at the speed of light. So travelling for a million years at the speed of light would feel instantaneous but when you emailed your family back home to let them know you arrived safely you would not get a reply as 1 million years would have passed.

 

[Particle Physicist]

I hope this doesn't get too long and I will try my best at explaining it, however, it is not intuitive and that is the hardest part. The reason it is not intuitive is that we don't spend our days traveling close to the speed of light.

Special relativity basically says, the laws of physics are the same in all uniformly moving reference frames. What does this mean? Lets take two distinct reference frames:

• Me stuck here on earth
• You traveling at 1/2 the speed of light in your private UFO

I measure the speed of light and get 186300 miles per second, no surprise, you also measure the speed of light and get the exact same number...

That's why its uncommon sense. That's not how things work at our level of normal every day existence. You would think that if you were traveling at 1/2 the speed of light, the speed you measure would be only 1/2 the speed of light because 2 halves make a whole.

So if we both get the same speed of light, even though you are traveling at 1/2 the speed of light, what gives? It turns out that time does, this effect is called Time Dilation.

I think the best way to explain this is Einstein's light clock example, imagine a box, at one end is a light source and at the other is a mirror. A tick of the clock is a pulse of light leaving the light source, bouncing off the mirror and returning to the light source. Here's the clock:

As you whizz by me at 1/2 the speed of light, I look in to your private UFO and see your clock, to me the light in your clock appears to be going in a zig-zag:

As the diagrams says, the light blip aboard your UFO goes further between ticks so each tick is spaced further apart and hence time for you passes slower relative to time for me.

What's very important here is neither one of us has the "correct" measure of time, that's what relativity says, all uniformly moving frames of reference are equally valid.

What happens if your UFO travels at the speed of light? The light from the light source never reaches the mirror hence, no tick, hence, time for you stops.

The problem here is that relativity also states that anything with mass cannot travel at the speed of light. A photon is massless hence travels at c and does not experience time. As I stated in my original post, imagine if we could block the particle that gives other particles mass, using Newton's first law we see that the inertia isn't an issue any longer and we could also travel at the speed of light (and be able to accelerate to it). If I wanted to build an object that performs the way UFOs are said to, decreasing mass substantially seems closer to being understood than anti-gravity.

Your sudoku quote is fantastic and I'm going to steal it . That's a lot of how theoretical physics works; as we are talking about special relativity lets bring up E=Mc2 - Energy is equal to the Mass multiplied by the speed of light squared. However lets reverse this equation, M=E/c2 - The LHC is in the news a fair bit lately and M=E/c2 is how it works.

M=E/c2 says is that if I pump in a lot of energy I can create mass. So a particle accelerator like the LHC takes two counter rotating streams of protons (Hydrogen nuclei) and pumps a lot of energy in to them to accelerate them to almost the speed of light, then slams them together. That energy becomes mass. It is not the case of slamming them together to see what comes out as I hear on the news, its much more exciting than that, as we are turning energy in to matter.

Further this is how we might detect extra dimensions, we know the energy we put in and we can measure the mass of what comes out. If those two values don't match (as M=E/c2 say they should) it is possible that some of that energy has escaped to another dimension.

Finally back to Superstring theory and friends that are in fact quantum theories of gravity. As physics goes on, it gets harder because new theories have to encompass the theories that came before them, relativity is a more accurate way of explaining the universe than Newtonian mechanics for example. One of the issues with Newtonian mechanics is action at a distance is instantaneous, we knew this not to be the case and general relativity corrects this. We know that relativity falls down when dealing with the very small, Quantum mechanics does a fantastic job of explaining the tiny, yet this doesn't work when going to the macro level. So we have two parallel theories that both explain their own areas well but don't explain the whole.

Superstring theory intends to unite these theories and is currently the only valid theory to do so, it is not finished but it is also not on the fringes of theoretical physics either. In the show David used the "it's just a theory" line, what else are theoretical physics mean to produce? Superstring theory has to encompass both general relativity and quantum mechanics which have been tested extensively so there is a huge body of evidence to check the predictions of Superstring theory against. People that don't realize this and think that these new theories are created in a vacuum. The basis of it has been around for a while, for example, in 1919 Kaluza did the maths of general relativity and added a 5th dimension, in true sudoku form, when he did this, out popped Maxwell's equations for electromagnetism thus unifying gravity and electromagnetism. Then again, Superstring theory could be wronger than wrong and that is even more exciting as there is new stuff to learn and no doubt by proving Superstring wrong we have learned something further.

Einstein genius was his creative thinking, a lot of the work for special relativity already existed (from FitzGerald & Lorentz for example), Einstein genius was taking the leaps and putting the jigsaw together. As Einstein said "Imagination is more important than knowledge".

 

[Drew UK]

Thanks for this erudite response, and in the most I completely understand the main theme - and all the maths/equations make perfect sense.
Since after all it has been proven with the atomic clock experiment where they measured the nanosec. time lag

But what I have trouble with is the light vs time issue?

What happens if your UFO travels at the speed of light? The light from the light source never reaches the mirror hence, no tick, hence, time for you stops.

Now could I not equally say - What happens if your UFO travels at the speed of sound? The sound from the sound source never reaches the mirror hence, no tick, hence, time for you stops. - But we don't, we say sound stops - hence the deafening silence on the concorde as it breaks the sound barrier.

So why could I not equally (correct, in my unimaginative mind) say - What happens if your UFO travels at the speed of light? The light from the light source never reaches the mirror hence, no tick, hence, light for you stops.

And to add another spanner into the works - has not light been slowed down in immense vacuums, in extreme low temperatures - so how can the speed of light be constant?

So I have a dichotomy in my mind at the moment that of this Relativity Theory (unpreffered) and a doppler effect (preffered) which one should be correct and why?
I hope you can understand where I am coming from, to put it in a different form how can we measure time when the instruments are measuring them by is affected by time itself - of course you say, because it's all relative - so then we start again......

Thanks, I hope you are teaching this stuff.

 

[Drew UK]

I need to elaborate on the atomic clock - I dont know what was used in the 1970's experiment to proof - but it measures time by the radioactive decay of Ceasium 133 - delta E = hV - so it travels from a source to a detector, again at speed and acceleration the distance which it needs to travel is longer (since once it is emitted from the source (speed from the source which travels at the same speed as the detector) the distance is increased beacuse it travels in between at free flight (not assisted by the speed of the equipment) to hit the detector because the detector is also been pulled forward at equal rate to the source - hence the time lag??? Help!!!
Maybe I need pictures - See doppler effect!!!

 

[Michael L.]

"Now could I not equally say - What happens if your UFO travels at the speed of sound? The sound from the sound source never reaches the mirror hence, no tick, hence, time for you stops."

No, the speed of sound is a much less important number and not really a constant. Sound must, unlike light, travel through a medium (an atmosphere usually) and differences in the medium result in differences in the speed of sound. There is no speed of sound in a vacuum! Let's be practical, though, and think about sound, which we know is not a barrier. It is much easier to mentally examine speed of sound related situations. For example: You race away from me in a jet at the speed of sound. I shoot you with a high powered rifle. The bullet will travel faster than sound... Will time stop for you merely because you will not hear the shot?

"And to add another spanner into the works - has not light been slowed down in immense vacuums, in extreme low temperatures - so how can the speed of light be constant?"

c, the speed of light in a vacuum, is the constant you are referring to but the speed of light is slower when in a transparent medium such as glass. c is, in popular science, as famous for being the "galactic speed limit" as it is for being a constant.

Y'all are going to inspire me to go back and finish my physics degree!

 

[Drew UK]

Tempus Fugit ??!!

 

[Particle Physicist]

Michael, defiantly finish your degree. It's such a fun field with a lot happening.

Drew, Michael is spot on with sound, you can't compare it to light in such a manner as it needs a medium of transference; sound is really vibrations of that medium that travels as a wave. We can pass the speed of sound easy, passing the speed of light is a much harder problem. When ever I talk about the speed of light, I mean in a vacuum, light does travel slower in other material based on the refractive index of the material.

The one thing that I have to be careful of is saying things in absolutes to make it easier to explain, for example I will says that things can't travel faster than light, this isn't strictly true in the world of Quantum Mechanics, for example Quantum Tunneling and there is also the issue of Quantum Entanglement (if you think special relativity is uncommon sense, try these).

The light clock is an Einstein thought experiment that explains what is happening. Lets go with the Atomic clock, in reality, because of the speed it is traveling at, time has in fact slowed for the Ceasium 133. It's still decaying at it's normal rate, the fact that it is moving relative to the clock on Earth means that it experiences time dilation. Damm, that doesn't help.

OK, lets try this; building on what Michael said in relation to the Einstein clock and why time stops. You're in your UFO flying past me at the speed of light which is a hard speed limit, exactly as you fly past I shoot a bullet at you from my speed of light rifle. Will the bullet hit you? Not until you slow down because the bullet and your ufo are both at the hard speed limit. OK, instead of the bullet, as you fly past at the speed of light, I'm looking in to your UFO at your light clock, what I see is the light from your clock horizontal between the mirrors.

See the diagrams above, where, from my point of view, the light is angled to reach the second mirror, well, when the ufo is traveling at c, that angle from my point of view would be 90 degree to the mirror, hence the photon will never reach the second mirror and from my point of view your clock doesn't tick.

Here's a couple of links, the first is to a torrent of some video lectures by Dr. Richard Wolfson, this is a fairly large size.

http://thepiratebay.org/torrent/3910586/TTC_VIDEO_-_Modern_Physics_For_Non-Scientists

In the torrent below you can find the same lectures in audio format hence a smaller download, there are a lot of different lectures in that torrent, the ones you are after are called: "Einstein's Relativity and the Quantum Revolution". If you use uTorrent it will let you skip all but the ones you want.

http://thepiratebay.org/torrent/3366311/The_Teaching_Company_lectures_(my_favorites)

I haven't listened to these myself but a colleague recommended them as a fun and interesting way to learn about the subject.

 

[Kieran]

Michael, defiantly finish your degree. It's such a fun field with a lot happening.

Drew, Michael is spot on with sound, you can't compare it to light in such a manner as it needs a medium of transference; sound is really vibrations of that medium that travels as a wave. We can pass the speed of sound easy, passing the speed of light is a much harder problem. When ever I talk about the speed of light, I mean in a vacuum, light does travel slower in other material based on the refractive index of the material.

The one thing that I have to be careful of is saying things in absolutes to make it easier to explain, for example I will says that things can't travel faster than light, this isn't strictly true in the world of Quantum Mechanics, for example Quantum Tunneling and there is also the issue of Quantum Entanglement (if you think special relativity is uncommon sense, try these).

The light clock is an Einstein thought experiment that explains what is happening. Lets go with the Atomic clock, in reality, because of the speed it is traveling at, time has in fact slowed for the Ceasium 133. It's still decaying at it's normal rate, the fact that it is moving relative to the clock on Earth means that it experiences time dilation. Damm, that doesn't help.

OK, lets try this; building on what Michael said in relation to the Einstein clock and why time stops. You're in your UFO flying past me at the speed of light which is a hard speed limit, exactly as you fly past I shoot a bullet at you from my speed of light rifle. Will the bullet hit you? Not until you slow down because the bullet and your ufo are both at the hard speed limit. OK, instead of the bullet, as you fly past at the speed of light, I'm looking in to your UFO at your light clock, what I see is the light from your clock horizontal between the mirrors.

See the diagrams above, where, from my point of view, the light is angled to reach the second mirror, well, when the ufo is traveling at c, that angle from my point of view would be 90 degree to the mirror, hence the photon will never reach the second mirror and from my point of view your clock doesn't tick.

Here's a couple of links, the first is to a torrent of some video lectures by Dr. Richard Wolfson, this is a fairly large size.

http://thepiratebay.org/torrent/3910586/TTC_VIDEO_-_Modern_Physics_For_Non-Scientists

In the torrent below you can find the same lectures in audio format hence a smaller download, there are a lot of different lectures in that torrent, the ones you are after are called: "Einstein's Relativity and the Quantum Revolution". If you use uTorrent it will let you skip all but the ones you want.

http://thepiratebay.org/torrent/3366311/The_Teaching_Company_lectures_(my_favorites)

I haven't listened to these myself but a colleague recommended them as a fun and interesting way to learn about the subject.

You remind me of that science guy from ufo hunters, i am being stupid here man dont mind me, you seem to be a interesting guy ,with good posts