I've just been listening on the radio to Professor Jim Al-Khalili, the University of Surrey Physicist and Radio 4 presenter.
He will co-lead a team which has just received a grant of £2.1 million to explore the fundamental nature of time.
The project is called, "Life on the Edge: quantum thermodynamics, quantum biology and the arrow of time".
US$3 million grant to the University of Surrey for research into nature of time and life itself | EurekAlert! Science News
Why does time have a direction for humans, while the sub-atomic particles from which they are made have no past and no future?
Maybe the team will find the answer! 😎
He will co-lead a team which has just received a grant of £2.1 million to explore the fundamental nature of time.
The project is called, "Life on the Edge: quantum thermodynamics, quantum biology and the arrow of time".
US$3 million grant to the University of Surrey for research into nature of time and life itself | EurekAlert! Science News
Why does time have a direction for humans, while the sub-atomic particles from which they are made have no past and no future?
Maybe the team will find the answer! 😎
Attachments
See here's the issue:
People think they know way more than they know.
Some Peoples (yes that is a word 🙄) more than others.
History shows this clearly.
The "evidence" for the universe expanding is just not there.
Equations are scalar (meaning, they apply to certain scales and also non-extreme situations, this is also scalar or a range).
It's somewhat morbid, but remember science progresses one funeral at a time. There are very good reasons for this saying.
It took surgeons/doctors decades to do something simple like start washing their hands after one doctor mentioned it to be statistically relevant and came up with a sound theory. And these were the "smart" people in the 19th century.
This actually happens all the time in debates:
A question is asked that has incorrect assumptions from the beginning: "What is the Universe expanding into?"
And this makes it harder to answer.
Guess it's called a "loaded question" I suppose.
People think they know way more than they know.
Some Peoples (yes that is a word 🙄) more than others.
History shows this clearly.
The "evidence" for the universe expanding is just not there.
Equations are scalar (meaning, they apply to certain scales and also non-extreme situations, this is also scalar or a range).
It's somewhat morbid, but remember science progresses one funeral at a time. There are very good reasons for this saying.
It took surgeons/doctors decades to do something simple like start washing their hands after one doctor mentioned it to be statistically relevant and came up with a sound theory. And these were the "smart" people in the 19th century.
This actually happens all the time in debates:
A question is asked that has incorrect assumptions from the beginning: "What is the Universe expanding into?"
And this makes it harder to answer.
Guess it's called a "loaded question" I suppose.
There is a nice entry in Wiki on Lagranians and why it has in some cases displaced Newtonian mechanics when describing the motioned of objects. In summary
“Instead of forces, Lagrangian mechanics uses the energies in the system. The central quantity of Lagrangian mechanics is the Lagrangian, a function which summarizes the dynamics of the entire system. Overall, the Lagrangian has units of energy, but no single expression for all physical systems. Any function which generates the correct equations of motion, in agreement with physical laws, can be taken as a Lagrangian. It is nevertheless possible to construct general expressions for large classes of applications. The non-relativistic Lagrangian for a system of particles can be defined by[1]”
Math is beyond my pay grade for the most part but here’s the link
Lagrangian mechanics - Wikipedia
“Instead of forces, Lagrangian mechanics uses the energies in the system. The central quantity of Lagrangian mechanics is the Lagrangian, a function which summarizes the dynamics of the entire system. Overall, the Lagrangian has units of energy, but no single expression for all physical systems. Any function which generates the correct equations of motion, in agreement with physical laws, can be taken as a Lagrangian. It is nevertheless possible to construct general expressions for large classes of applications. The non-relativistic Lagrangian for a system of particles can be defined by[1]”
Math is beyond my pay grade for the most part but here’s the link
Lagrangian mechanics - Wikipedia
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I'll leave that link till later, Bonsai.
Today, I'm more interested in the energy and dynamics of the Olympic gymnasts.
Their motion often appears to defy the laws of physics!
Today, I'm more interested in the energy and dynamics of the Olympic gymnasts.
Their motion often appears to defy the laws of physics!
Here's a simplification based on what I've gleaned from my research:
Instead of thinking of motion as being a result of forces as described in Newton's laws, Lagrangian mechanics describes motion in terms of energies.
Lagrangian mechanics is based on two fundamental concepts:
- The Lagrangian which describes motion through kinetic and potential energy.
- Action, which describes a path or trajectory through space and time.
Unlike total energy (T + V), which is a conserved quantity, the Lagrangian (T -V) changes over time, making it a much more useful tool for measuring motion.
Action is defined as the integral (sum) over time of the Lagrangian at each point in the trajectory. Physical objects move in such a way that the action is minimised or stationary.
At this point in my research my brain exploded
so here's a link to 'Lagrangian Mechanics for Dummies' for the rest of the story:Lagrangian Mechanics For Dummies: An Intuitive Introduction – Profound Physics
And here are the key differences between Lagrangian mechanics and Newtonian mechanics:
Lagrangian vs Newtonian Mechanics: The Key Differences – Profound Physics
There's a second formulation beyond Newtonian Mechanics, and that is Hamiltonian Mechanics:
Hamiltonian mechanics - Wikipedia
Built around T+V is constant, i.e. Conservation of Energy. Rather than T-V in Lagrangian.
Also deals with Momentum Rather than Velocity.
I seem to remember their is a third one named after a Frenchman, but it has slipped my mind. We also have the unproven MOND system, Modified Newtonian Dynamics, where gravity doesn't obey inverse square.
Anywhoo, I wanted to address Jimmy154 qualms about the Universe really expanding. Doctor Becky explains what it is or isn't expanding into at 3m in this video. Also takes on Dark Matter.
An Astrophysicist's Top 10 Unsolved Mysteries - YouTube
Issues about a greater than expected expansion of Space are addressed here:
The mystery of how big our Universe really is - BBC Future
No, I don't fully understand it all myself. But then my name isn't Einstein.... 😀
Hamiltonian mechanics - Wikipedia
Built around T+V is constant, i.e. Conservation of Energy. Rather than T-V in Lagrangian.
Also deals with Momentum Rather than Velocity.
I seem to remember their is a third one named after a Frenchman, but it has slipped my mind. We also have the unproven MOND system, Modified Newtonian Dynamics, where gravity doesn't obey inverse square.
Anywhoo, I wanted to address Jimmy154 qualms about the Universe really expanding. Doctor Becky explains what it is or isn't expanding into at 3m in this video. Also takes on Dark Matter.
An Astrophysicist's Top 10 Unsolved Mysteries - YouTube
Issues about a greater than expected expansion of Space are addressed here:
The mystery of how big our Universe really is - BBC Future
No, I don't fully understand it all myself. But then my name isn't Einstein.... 😀
Apparently, the Lagrangian is simply a mathematical tool for describing motion, but it doesn’t have any physical or observable meaning.
In contrast, Hamiltonian mechanics has a significant physical meaning as it represents the total energy of a system and so is important for energy conservation, as Steve says.
Hamiltonian mechanics is also important for describing how the system changes or evolves with time. This makes it pretty important for quantum mechanics as well as thermodynamics.
I read about it here: Hamiltonian Mechanics For Dummies: An Intuitive Introduction – Profound Physics
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Earlier in the thread, I looked at the observational evidence for the expansion of spacetime and stated that our current data base is not yet reliable enough to make an accurate determination of the rate of expansion.
Expansion is allowed by the mathematics of general relativity, but we still have a way to go before we can be sure of exactly what's going on.
Those are very nice links Galu - clear explanation. Interesting how Lagranians ‘recast’ Newton’s force vector with energy-path view to describe a systems dynamics.
The hope being that data obtained from the combined emission of light and gravitational waves resulting from at least 50 neutron star collisions will provide a third, precise measurement of the 'Hubble Constant'. However, it may take some time to collect that amount of data.
As things stand, Dr. Becky obviously agrees with my statement that the current data base used to measure the expansion of the universe is unreliable!
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What if the background radiation was not the result of the big bang?
What if the red shift was not because the distant light source was moving away?
The light could be loosing energy as it travels through the medium of space and this energy is re-emitted as the microwave background. You know that space is packed full of electrons and positrons going in and out of existance. They only add up to net zero.
I liked Stephen Hawking but he was really a mathematician. What with dark matter and dark energy there are too many fudges in cosmology.
What if the red shift was not because the distant light source was moving away?
The light could be loosing energy as it travels through the medium of space and this energy is re-emitted as the microwave background. You know that space is packed full of electrons and positrons going in and out of existance. They only add up to net zero.
I liked Stephen Hawking but he was really a mathematician. What with dark matter and dark energy there are too many fudges in cosmology.
There is no evidence that photons lose energy through interaction with the medium of space. Photons can scatter off interstellar electrons, but they do not lose energy in the process.
Neither does a photon which is red-shifted by the expansion of space actually lose energy.
Suppose an observer travelling along with a distant galaxy sees a photon in the yellow part of the spectrum. By contrast, an observer situated at a point from which the galaxy is receding will see the same photon in the red part of the spectrum.
However, the red-shifted photon has not lost any energy. The principle of conservation of energy is not violated since the two observers are making their measurements in different reference frames.
Fermilab | Science | Inquiring Minds | Questions About Physics
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With long fibre optic transmission there is Raman shift, caused by the photon interacting with the material. This a problem for data transmission because the wavelength of transmitted photons increase by varying amounts so there is a spreading. More data can be carried on a fibre by multiplexing, but this spread reduces the amount of channels available.
Although there is no experiment to test this hypothesis it would seem probable that light traveling through space would behave in a similar way. Not that doppler is irrelevant just that asuming more red shift with greater distance is down to expansion is an asumption. The predicted background radiation is not coincidental, but not strong enough evidence to be conclusive.
Although there is no experiment to test this hypothesis it would seem probable that light traveling through space would behave in a similar way. Not that doppler is irrelevant just that asuming more red shift with greater distance is down to expansion is an asumption. The predicted background radiation is not coincidental, but not strong enough evidence to be conclusive.
You appear to be referring to Raman scattering, so I researched it a bit. 😎
By transparent material, we are referring to the likes of glass rather than space, which I would think is unlikely to have these "high frequency vibrational modes".
I did optical fibres at College in Telecoms. You use Bessel Functions as the cylindrical solution if I recall:
Bessel function - Wikipedia
Forgotten it all, TBH. 😱
Anyway, how's about a NEW theory of the Universe? Always good. Larry Silverberg explains.
Fragments of energy – not waves or particles – may be the fundamental building blocks of the universe
The Universe may be fuzzy balls or fragments of Energy. It works apparently. Assume these balls of Energy have a 1/r distribution and you correctly calculate the bending of light and the precession of the Perihelion of Mercury. Which is General Relativity. Always a bit dubious about 1/r relations because therein lurk infinities, but no worse than Newtonian gravity or classical electrostatics.
The PDF is available for Gratis on the second page of downloads at colleague Jeffrey Eischen's page which is linked. Otherwise you pay $25 for it. It's cast in the wretched Vector Algebra complete with the horrid Curl function, but the calculations are explained.
I could do a semester on that one. Looks my sort of thing. 🙂
Bessel function - Wikipedia
Forgotten it all, TBH. 😱
Anyway, how's about a NEW theory of the Universe? Always good. Larry Silverberg explains.
Fragments of energy – not waves or particles – may be the fundamental building blocks of the universe
The Universe may be fuzzy balls or fragments of Energy. It works apparently. Assume these balls of Energy have a 1/r distribution and you correctly calculate the bending of light and the precession of the Perihelion of Mercury. Which is General Relativity. Always a bit dubious about 1/r relations because therein lurk infinities, but no worse than Newtonian gravity or classical electrostatics.
The PDF is available for Gratis on the second page of downloads at colleague Jeffrey Eischen's page which is linked. Otherwise you pay $25 for it. It's cast in the wretched Vector Algebra complete with the horrid Curl function, but the calculations are explained.
I could do a semester on that one. Looks my sort of thing. 🙂
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