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24-01-2020, 09:06   #76
oriel36
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Okay. Do you have a worked example of observations of Mercury's orbit using the method you espouse?
People are so cool as they attempt to make sense of empirical crap and waste their imagination on that account. The fact is that they can now move on or back to astronomy as it was originally practiced by enjoying how we come to understand the faster moving Mercury and Venus as seen from a slower moving Earth -

https://www.youtube.com/watch?v=w2uCtot1aDg


Forensics is a genuine chore but necessary at present to clear out the voodoo merchants.

The crown jewel of theorists is meant to be the inverse square law as they call it but it was an attempt to fit astronomical predictions into a celestial sphere framework that emerged with accurate clocks in the late 17th century. This 'clockwork solar system' is a timekeeping contrivance which allows observers to predict astronomical events like transits as exact times and dates within the 365/366 day calendar system and comes down to us today as RA/Dec. It is further away from heliocentricity as the geocentric system was as it puts the Sun in a wandering motion along with the planets -

http://community.dur.ac.uk/john.luce...solar_year.gif


Newton attempted to make astronomical predictions look like experimental predictions which is why none of his followers have the slightest idea how to interpret observations and motions in space and make nuisances of themselves with their 'no centre/no circumference' celestial sphere universe that even the geocentric astronomers hated -

"And wherever anyone would be, he would believe himself to be at the
centre. Therefore, merge these different imaginative pictures so that
the center is the zenith and vice versa. Thereupon you will see--
through the intellect..that the world and its motion and shape cannot
be apprehended. For the Universe will appear as a wheel in a wheel and
a sphere in a sphere-- having its center and circumference
nowhere. . . " Nicolas of Cusa, 15th century

What is people like to say ? - garbage in and garbage out which sums up astrophysics while genuine astronomy is there for everyone else. The whole purpose is that the shelf life of voodoo merchants has passed with too many images and time lapse observations to enjoy. I am sure you will have a die-hard audience but they also haven't shown much confidence or competence in the relevant areas.
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24-01-2020, 10:44   #77
Fourier
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So the answer is no, you don't have detailed observations of Mercury using your method.
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24-01-2020, 10:59   #78
ps200306
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oriel36 has no intention of answering your question. His only aim is to troll yet another thread with mad ideas about the planets, as he has done 43 times so far on this recent one and many hundreds of times elsewhere over a period of years. He will never answer a direct question, and seems incapable of analytical thought. No coherent conversation with him is possible as he will just write the same nonsense over and over no matter what he is asked. Attempts to engage with him are futile and can only result in another wrecked thread.

Last edited by ps200306; 24-01-2020 at 11:02.
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24-01-2020, 11:02   #79
Fourier
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oriel36 has no intention of answering your question. His only aim is to troll yet another thread with mad ideas about the inner planets, like he has done 43 times so far on this recent one, and hundreds of times elsewhere over a period of years. He will never answer a direct question, and seems incapable of analytical thought. No coherent conversation with him is possible as he will just write the same nonsense over and over no matter what he is asked. Attempts to engage with him are futile and can only result in another wrecked thread.
Thanks! 43 times Jaysus!

If anybody wants to discuss actual cosmology or quantum theory I'm happy to talk.
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24-01-2020, 11:12   #80
oriel36
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So the answer is no, you don't have detailed observations of Mercury using your method.
To be fair, people no longer have an interest in Royal Society voodoo but if they choose to pursue how society spent 100 years following 'The Time Machine' fiction novel as facts they are better off looking at a work of fiction which contained a commentary on the Victorian mathematicians and their excesses -

https://www.newscientist.com/article...erland-solved/

Mathematicians today following these Victorian mathematicians pride themselves in their non-descriptions which is basically the chesire cat as Lewis Carroll saw them -

https://www.catster.com/lifestyle/ch...-lewis-carroll


Any value of forensics is back at the juncture where geocentricity and heliocentricity meet as some of the difficulties for genuine astronomers at that time were far too complex and intricate to deal with so they did their best. I can only go so far dealing with the forensics where experimental theorists that began with Newton hijacked astronomy but as a topic it is throwing good information after bad and ultimately counter-productive for today's world.

Nobody needs time,space and motion defined for them as Sir Isaac tried to do but if people choose to inspect how that icon was defining things to suit themselves they can go through the descriptions here and have a good old laugh at the attempted distortions he tried to impose on genuine astronomical methods and insights.

No offence, but conversing with a parrot ain't my idea of a conversation so it ends just as predicted.
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24-01-2020, 13:20   #81
ps200306
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If anybody wants to discuss actual cosmology or quantum theory I'm happy to talk.
I've got a question about the fundamental entities in QFT, if you don't mind. I just about got my head around pure states in wave mechanics being represented by basis vectors in a Hilbert space. The state vector can be used in a sandwich integral along with the appropriate operator to yield expectation values for observables. I've read that sandwich integrals are also used in QFT but that the quantum states are "operator valued". What does that mean? I've also heard about constructor and destructor operators in QFT but can't envisage how they arise. (I've got this book on my shelf but haven't made it past Chapter 0 yet ).
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24-01-2020, 16:56   #82
Fourier
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I've read that sandwich integrals are also used in QFT but that the quantum states are "operator valued". What does that mean?
There can be a bit of confusion in how this is explained in many places on the net, so what I say here might not match with some places online. That's simply because they're wrong. It will match textbooks on QFT like Peskin and Schroeder. The first thing to say is that the states are not operator valued but the fields.

So basically as I assume you know operators can act on states. In basic quantum mechanics the operators are things like momentum, position, Energy etc. Later you might encounter things called POVMs. These are observables that don't correspond to any classical quantities.

In classical field theory you have object like the electric field, the magnetic field and so on. Just like how position in classical mechanics become operators in quantum mechanics, so do the fields in Classical Field Theory become operators in Quantum Field Theory.

Where as the fields in the classical field case are number or vector etc valued at each point, the fields in quantum field theory are operator valued at each point. That operator representing observing the value of the field at that point.
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24-01-2020, 17:08   #83
oriel36
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The two boys suffer from the 'cheshire cat syndrome' as mathematical abstractions were always destroyed by reasonable people despite the hype -

"These are the imaginings of incomplete- notions-philosophers who make space an absolute reality. Such notions are apt to be fudged up by devotees of pure mathematics, whose whole subject- matter is the playthings of imagination, but they are destroyed by higher reasoning" Leibniz

What is a badge of honour among these voodoo spouting cretins is merely an invalid doctrine that doesn't stand up to the astronomers and those who find inspiration in the celestial arena -

"The phrase ‘grin without a cat’ is probably not a bad description of pure mathematics. Although mathematical theorems often can be usefully applied to the structure of the external world, the theorems themselves are abstractions built on assumptions that belong to another realm remote from human passions. Bertrand Russell once put it as, ‘remote from the pitiful facts of nature … an ordered cosmos, where pure thought can dwell as in its natural home, and where one, at least, of our nobler impulses can escape from the dreary exile of the actual world.’"

https://www.catster.com/lifestyle/ch...-lewis-carroll


The shelf life of chasing wordplays should be over for those who should use their reasoning and imaginative faculties in areas where these inept people cannot. Welcome to the 21st century !.

Last edited by oriel36; 24-01-2020 at 17:17.
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24-01-2020, 17:36   #84
mosii
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I think Feynman was right, no one truly understands Quantum Mechanics or even Quantum field theory.I certainly dont, but i still think eventually there will be some sort of unified theory,which will go a long way to enlighten things, to me anyway,thanks for info guys.
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25-01-2020, 07:34   #85
oriel36
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Dealing with the Victorian notions of spacetime was pointless as it amounted to a discussion why a cartoon or fictional world doesn't exist and throwing good information after bad.

I even dealt with the idiotic Mercury notion well over ten years ago and from what I can tell, even the mathematicians see how irrational it is and don't appeal to it anymore -

If Mercury is observed to have a deviation and then a solution is applied where one is also given for the Earth, the solution for the Earth must then be applied
to the observation of Mercury which, in turn, produces ever diminishing returns in a back and forth reduction in values.
-

[[discussing perihelion advance of various planets]] in Ohanian and
Ruffini (1994)
GR observed
Mercury 42.98 43.1 +-0.1
Venus 8.65 8.62
Earth 3.85 3.84
Mars 1.36 1.35

Thankfully this is not throwing good information after bad but a dead end unless people insist on suspending their common sense.
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25-01-2020, 10:17   #86
ps200306
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In classical field theory you have object like the electric field, the magnetic field and so on. Just like how position in classical mechanics become operators in quantum mechanics, so do the fields in Classical Field Theory become operators in Quantum Field Theory.

Where as the fields in the classical field case are number or vector etc valued at each point, the fields in quantum field theory are operator valued at each point. That operator representing observing the value of the field at that point.
So is QFT an extension of wave mechanics to include fields, i.e. we still have the old operators plus additional ones for fields? I presume that means the fields themselves are quantised? But hang on, the Hamiltonian in wave mechanics includes a potential term which would be determined by a -- now quantised -- field value. How do we then find energy eigenvalues for a given state? Just had a light bulb moment, possible a very dim one -- is this where renormalisation comes in?
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27-01-2020, 10:34   #87
Fourier
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So is QFT an extension of wave mechanics to include fields, i.e. we still have the old operators plus additional ones for fields?
Yes, although usually we don't keep the old ones as fields can describe particles as well.

Take the hydrogen atom as an example.

In wave mechanics hydrogen is modelled with the electron being a quantum particle with operators and the Coulomb field is just a classical field.

If you half apply QFT the electron is modelled the same way and the Coulomb field is quantised and described by quantum operators.

However if you fully use QFT the wave mechanics picture of the electron itself is replaced. The electron is modelled with a quantised electron field, just like the Coulomb field is quantised. So the old operators are gone.

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Originally Posted by ps200306 View Post
I presume that means the fields themselves are quantised?
Yes. Where quantised means being described with a quantum mechanical operator.

Quote:
How do we then find energy eigenvalues for a given state?
Finding energies in QFT is usually so difficult we don't do it. It requires completely different techniques from those used in wave mechanics. Usually QFT is only used to model particle scattering, as using it to work out things like the spectrum of hydrogen is so difficult. For that we use the simpler wave mechanics as you know.

Quote:
Just had a light bulb moment, possible a very dim one -- is this where renormalisation comes in?
Renormalisation is a bit technical, but basically when you quantise fields how multiplication works is very complicated. Renormalisation is the mathematical framework for how to multiply quantised fields.
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