1

Physics, Astronomy & Cosmology / Re: Is gravity down to curved spacetime, or gravitons?

« on: 07/04/2014 03:14:57 »

Mark Beardmore asked the Naked Scientists:
   
My question is about gravity. Einstein taught us that gravity is a warping of spacetime which causes objects to describe a curved path in the presence of matter. On the other hand, quantum mechanics tells us that gravity is communicated by tiny particles (gravitons) zipping backwards and forwards between two objects.
How can both be true? Please enlighten me.

Thank you for the wonderful podcasts you produce.

Mark Beardmore
Bristol, UK.
What do you think?

They are both supposed to be right and looked at from different points of view. Einstein's general theory of relativity is a classical theory which describes the gravitational field whereas quantum theory describes the mechanism of gravity.

re - Einstein taught us that gravity is a warping of spacetime which causes objects to describe a curved path in the presence of matter. - That is a myth. Einstein never taught us that. That's a common misconception about Einstein. While it's true that spacetime is curved in regions of spacetime where there are tidal gradients, gravitational fields can also be present in flat spacetime. It's wrong to think of curved spacetime as a actually being synonymous with gravity.

So there's no problem with them both being right.  Einstein describes gravity with his field equations while quantum gravity describes the mechanism of the gravitational interaction.

2

New Theories / Re: Are versions made of smaller particles?

« on: 06/04/2014 22:17:17 »

Both statements are the same to me, if you are talking about the same particle that is measured.

They are definitely not the same.

3

New Theories / Re: How gravity works, Spacetime is Gravity

« on: 06/04/2014 20:55:57 »

And Pmb,  You come on a thread of discussion,, of new ideas,, possibilities,, that do not break scientific law,, and you say it's wrong,,

No. I show you and explain what's wrong. But you don't understand physics well enough to understand the explanation so you insult me. I've placed you in my ignore list so I don't see the garbage and childish insults you toss out when I prove you wrong. If you were willing to learn then you'd have a place here but since you're not willing to learn then that will never happen.

And since you aren't worth thinking about you never had to worry about me contacting you again.

Grow up.

4

New Theories / Re: The Earth IS Flat

« on: 06/04/2014 19:40:05 »

Below is my theory that supports the Earth having a flat surface.

I'm sorry, but that make no sense whatsoever. There is no logical argument here.

5

New Theories / Re: Are versions made of smaller particles?

« on: 06/04/2014 16:59:18 »

- light acts as a particle and a wave simultaneously

That's incorrect. In fact you have in backwards. Photons can act as a particle or wave but never at the same time.

Also, this thread belongs in the New Theory forum, not here.

This is one of several experiments that concluded this statement:

http://www.sciencedaily.com/releases/2012/11/121101141107.htm

Don't believe everything that you read. That page says

Surprisingly, when a photon is observed, it behaves either as a particle or as a wave. But both aspects are never observed simultaneously. In fact, which behaviour it exhibits depends on the type of measurement it is presented with.

This is a new result and has to stand the test of time. However that doesn't mean that we were wrong all along and that things like electrons and photons always behave like a particle and a wave a the same time. At best this means that the found a case where that's not true.

The author of that page says something quite wrong too, i.e.

For instance, quantum theory predicts that a particle (for instance a photon) can be in different places at the same time. In fact it can even be in infinitely many places at the same time, exactly as a wave.

That is total nonsense. Quantum theory does not say that. It says that there is a finite probability that a particle can be measured in infinitely many places at the same time.

An acquaintance of mine (also a physicist) used to teach QM and is now the author of a famous QM textbook author. Let me bounce this off of him and I'll get back to you.

6

New Theories / Re: How gravity works, Spacetime is Gravity

« on: 06/04/2014 16:25:11 »

Even the name of this thread tells how wrong it is. Spacetime exists in the absence of gravity but gravity cannot exist in the absence of spacetime. If you chose to study physics and GR before you made started threads like this then you wouldn't keep making these mistakes.

7

New Theories / Re: Time is different for everyone?

« on: 06/04/2014 16:21:21 »

..and time seems to pass quicker as you get older.

This one is easy to explain. When you're younger, one year is a large fraction of your life up until that post.  Then, later on in life, time seems to pass by faster.

Going from 5 to 6 years old took 1/5 th the amount of your life at that point. Going from 50 to 51 took 1/50 th the amount of your life at that point.

8

New Theories / Re: Time is different for everyone?

« on: 06/04/2014 16:16:13 »

(By the way Pmb, I didnt see anyone make a reference to Pot, other than you??) 

That's because the thread in which it was mentioned was deleted.

9

New Theories / Re: Are versions made of smaller particles?

« on: 06/04/2014 16:07:26 »

- light acts as a particle and a wave simultaneously

That's incorrect. In fact you have in backwards. Photons can act as a particle or wave but never at the same time.

Also, this thread belongs in the New Theory forum, not here.

10

Physics, Astronomy & Cosmology / Re: How photons collide?

« on: 06/04/2014 16:00:12 »

I showed that the reverse reaction doesn't happen, so, clearly it's not possible to reverse the equations...

No. You did no such thing. You made an error in that post. This is what you said

You can't make photons into an e- e+ pair if their total energy is less than 1022 keV and if they don't hit other particles (such as nuclei) to keep momentum conservation.

That is quite wrong. The process of making an electron-positron pair from two photons is possible and is referred to as photon pair production or pair creation. See this as an example at http://en.wikipedia.org/wiki/Pair_production

See also An Introduction to Quantum Field Theory by George Sterman, page 217.

You implied that an electron can't collide head on with a positron and in the process produce two photons moving in opposite directions with the same energy because momentum won't be conserved. That's clearly wrong. You made the mistake of thinking that there had to be another particle present to act like a catalyst in order to take up some  momentum in order for momentum to be conserved. It seems that you're confusing this with pair production use in a single photon to create an electron-positron pair. In such a case you'd be right. The appropriate analogy would then be for an electron to annihilate a positron and produce a single photon.

You're quite wrong. A photon can collide with another photon and produce an electron-positron pair. This is referred to as "Matter Creation" in Wikipedia and is listed under http://en.wikipedia.org/wiki/Matter_creation

See also - http://web.pdx.edu/~egertonr/ph311-12/pair-p&a.htm

The example given by the OP, namely photon pair production, is described by the equation; photon + photon -> electron + positron which is quite possible and is called photon pair production.

11

New Theories / Re: How gravity works, Spacetime is Gravity

« on: 06/04/2014 13:37:21 »

I have nothing to prove to ignorant trolls like you. And if you wanted to see what I know then search the forum. I won't discuss anything like you. You don't understand physics well enough to be able to understand what I'd be writing.

For example: You don't demonstrate enough knowledge to know what is contained here
http://home.comcast.net/~peter.m.brown/sr/sr.htm
http://home.comcast.net/~peter.m.brown/gr/gr.htm
http://home.comcast.net/~peter.m.brown/math_phy/math_phy.htm

Now, go away troll.

12

Physics, Astronomy & Cosmology / Re: How fast is a black hole spinning?

« on: 06/04/2014 12:27:23 »

It is not possible (or necessary) to measure the angular velocity of the singularity.

It's more than just that. It's not even possible to define it. One would have to give meaning to such a thing and that can't be done with a singularity.

13

New Theories / Re: GENERAL RELATIVITY IS WRONG

« on: 06/04/2014 04:24:08 »

DanielB’s nonsense above is one of the reasons why I'm won’t correspond with him. I.e. he’s incapable of understanding what people write. In this case he constantly twists my words. For example, he wrote

Pmb, the appearance of curved space time is a well known fact,,

This is the worst kind of nonsense that appears in these forums. It’s known as a straw man and is defined as follows. From http://en.wikipedia.org/wiki/Straw_man

A straw man, also known in the UK as an Aunt Sally, is a common type of argument is an informal fallacy based on the misrepresentation of the original topic of argument. To be successful, a straw man argument requires that the audience be ignorant or uninformed of the original argument.
The so-called typical "attacking a straw man" implies an adversarial, polemic, or combative debate, and creates the illusion of having completely refuted or defeated an opponent's proposition by covertly replacing it with a different proposition (i.e., "stand up a straw man") and then to refute or defeat that false argument, ("knock down a straw man,") instead of the original proposition.

In this context he is implying that I don’t know that spacetime exists. I never said that of course. The term “appearance” means “a way of looking that is not true or real”. Spacetime curvature IS real. When he posted his claim about curvature being an appearance it was he who was in error because it means that spacetime curvature is not real and that’s wrong.
DanielB claimed that something “gave the appearance” of curvature. From his last response it now seems clear that he doesn’t know what word “appearance” means. I guess that his problem is Daniel’s problem is his understanding of English.

Moving on. When he made the claim

...curved space time is a well known fact,, called gravitational lensing,...

it demonstrates his poor understanding of GR. I.e. when he said "...called gravitational lensing," he was implying that spacetime curvature and gravitational lensing are one in the same thing, and they are not. Spacetime curvature is merely the relativistic term for tidal gradients. Gravitational lensing is the phenomena of light being deflected by the sun and forming an image which is an enlarged version of the original
Then he went on and misused GR terminology. E.g. he claims

...and that is (ONLY) done through the appearance of curved spacetime around any steller object of matter and mass, and due to it's amount of spacetime displacement.

He incorrectly used the term "spacetime displacement" to be synonymous with "spacetime curvature" when in fact they are very different terms. Spacetime displacement is what one would call the end result of tracing out a displacing a point in spacetime. E.g. During the time interval dt that it took to write the term "word," my computer underwent a displacement in spacetime from (t, x, y, z) => (t + dt, x, y, z) (x,y,z didn't change because my  computer remain fixed in space during that time period).
(t, x, y, z) => (t + dt, x, y, z) is an example of a spacetime displacement. As anyone can see, this is not the same thing.
Then you posted this nonsense/lie

According to you,,  You cannot distort / displace spacetime.

So again, either he’s unable understand/grasp what he’s writing or he’s lying.
This led you to the most ignorant comment I've seen him make to date, i.e. he wrote
[quote author = DanielB]
So we need to toss out Einsteins General Relavity?
[/quote]
I never made such statement and never would either. This is demonstrated by the fact that I proof read the original versikon of Exploring Spacetime, which is the text used at MIT in one of their courses on relativity.
I've written some tutorials on GR at http://home.comcast.net/~peter.m.brown/gr/gr.htm
See also "Einstein's gravitational field" by me at http://xxx.lanl.gov/abs/physics/0204044
Now he’s posting childish things such as

Alan, Pmb not once,, on any thread I have read,, has stated his (knowledge)

That’s right. Not to your knowledge. However I’ve been posting in this forum for many years and everyone in this forum knows such a thing to be false. If you wanted to know about my knowledge then all you had to do was ask. My website at http://home.comcast.net/~peter.m.brown/ and contains descriptions that I created of various things that I’ve had to explain to people here.
I also proof read the text Exploring Black Holes by Taylor and Wheeler. The first version was published in 2000. I've been proof reading the second version this past year or so too. That book is online at at http://www.eftaylor.com/comments/
Then you go on with more childish nonsense like

I don't foresee his/him every standing behind his statements with either , fact, theory or hypothesis.

This is nonsense. Everyone here knows my reputation and they ALL know that's exactly what I do, i.e. I do post fact, theory, etc. Even the moderators know that. If someone wanted me to explain something, all they have to do is ask.

He will ever, start calling person names however, when you ask him to explain anything he says

This is a lie and is one of the things that make you a troller.  DanielB doesn’t understand the difference between name calling and using terms which are descriptive to referring to comments he makes.

14

Physics, Astronomy & Cosmology / Re: How photons collide?

« on: 06/04/2014 03:31:43 »

Eh, no!   []  You can't make photons into an e^- e⁺ pair if their total energy is less than 1022 keV and if they don't hit other particles (such as nuclei) to keep momentum conservation.

I don't understand the purpose of this comment. His comment didn't indicate otherwise, so why bother mentioning it? When information is input out of the blue of no apparent reason it only serves to confuse.

15

Physics, Astronomy & Cosmology / Re: What was concluded about the fossilised bacteria in the Mars meteorite?

« on: 06/04/2014 03:25:40 »

Derek asked the Naked Scientists:
   
I remember the widespread media coverage regarding the Martian meteorite ALH84001, back in 1996.

Researchers were suggesting that certain features in there resembled micro-fossils - i.e. evidence for life on Mars. For some time it was possible to follow the debate back and forth, but it is a long time ago now and it has all gone quiet.

Was there ever a conclusion to this debate?

Thanks,
Derek McComiskey

What do you think?

See http://en.wikipedia.org/wiki/Martian_meteorite

This meteorite received much attention after an electron microscope revealed structures that were considered to be the fossilized remains of bacteria-like lifeforms. As of 2005, scientific consensus was that the microfossils were not indicative of Martian life, but of contamination by earthly biofilms. However, in 2009, new analyses ruled out earthly and non-biological origins, presenting strong evidence of life on Mars.[18] ALH 84001 is as old as the basaltic and intermediate shergottite groups — i.e., 4.1 billion years old.

16

Physics, Astronomy & Cosmology / Re: Do photons at light speed experience time stopping?

« on: 05/04/2014 13:57:17 »

...
'science' is full of them, 'myths'
if 'science' repeats a myth enough, people start believing it, and the myth becomes fact.
It's all a scam.

At least this is true in your case...

Please don't feed the trolls.

17

The Environment / Re: Have you ever experienced Driving through a rainbow....?

« on: 05/04/2014 11:00:44 »

I can't say exactly what it was that you experienced but it's not possible for someone to actually be inside a rainbow because they don't have a particular location but only exist according to an observer, whether the observer is a camera or you eye.

After I read this more carefully I'll try to figure out exactly what it was you saw.

18

Physics, Astronomy & Cosmology / Re: How fast is a black hole spinning?

« on: 05/04/2014 10:53:14 »

Søren Ragsdale asked the Naked Scientists:
   
I've heard that black holes spin, which causes frame dragging. I'm not sure what that means, though.

If we talk about a bicycle wheel, its "rotations per minute" measure how fast the tire travels around its axle. But a singularity inside the event horizon of a black hole is a point, it has zero radius.

How can we say how fast a black hole's singularity is spinning if it has zero radius?
What do you think?

I'm not 100% sure but I believe that black hole rotation isn't quantified in terms of angular velocity. It's quantified in terms of angular momentum.

19

New Theories / Re: GENERAL RELATIVITY IS WRONG

« on: 05/04/2014 04:39:56 »

I disagree with that statement, if the graviton did not travel with the photon. It would be unaffected by a gravity field, and travel straight. As I said different things can have the same affect it gives the appearance of a curve space when the photon bends in a gravity field.

First off, the photon does move with the speed of light so there's no cause to consider "if" statements like that.

"It would be unaffected by a gravity field, and travel straight." - No particle has that ability, none. Not in the presence of a gravitational field.

"As I said different things can have the same affect it gives the appearance of a curve space when the photon bends in a gravity field." - Such as?

BTW - Nothing can give the "appearance" of a curved spacetime.

20

Physics, Astronomy & Cosmology / Re: Do photons at light speed experience time stopping?

« on: 05/04/2014 04:26:44 »

just a cop out,

You sound like a teenager who thinks he knows everything and I certainly won't waste anymore time with a ignorant troller like you.

Folks - Why are we bothering with this person? He's obviously a good for nothing troller and not worthy of recognizing his/her presence here. Forget this idiot and let's get back to discussion between intelligent, mature people and not the likes of this troller.