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Questions related from Hossein Javadi
One of the challenges of modern physics is the astounding role of mathematics in physics. So that some physicists claim that physics is lost in...
03 March 2019 9,959 54 View
“It’s still possible that photons have mass, and therefore (ironically) don’t move at the speed of light. That’s not quite as crazy as it sounds. As you’d expect, though, even a tiny photon mass...
07 July 2018 8,458 9 View
“Those photons are said to be virtual because the ground state cannot radiate. Their presence can be however directly revealed when the system parameters are non-adiabatically modulated in time,...
06 June 2018 2,994 26 View
The speed of gravity is one of the unresolved physics problems. Although for the first time Newton has introduced force into mathematical equations of physics, it was discussed long time ago....
05 May 2018 10,058 0 View
Galileo was the first scientist who has tried to measure the speed of light but failed. Although the Galileo 's method to determine the speed of light was very primitive, it was precisely a...
04 April 2018 6,370 0 View
This is a wonderful question … in the first instance, it’s answered by Einstein’s theory of general relativity. (Spoiler alert, light travels along geodesics, which are approximately straight...
04 April 2018 8,704 0 View
In quantum mechanics, "electrons can absorb energy from external sources, such as lasers, arc-discharge lamps, and tungsten-halogen bulbs, and be promoted to higher energy levels. This tutorial...
03 March 2018 6,570 27 View
There is still no consensus on whether the fields are composed of particles or no. For examples: Art Hobson, There are no particles, there are only fields, American Journal of Physics 81, 211...
02 February 2018 9,719 11 View
A pulse of light carries energy and momentum, and it is deflected by the gravitational field of a massive body. Then, according to Newton's 'actio equals reactio', it is also a source of a...
01 January 2018 9,456 38 View
In 1924 de Broglie assumed that for particles the same relations are valid as for the photon: E=hf and E=pc Where E and p are the energy and momentum of the...
01 January 2018 4,698 36 View
The Standard Model of particle physics describes the universe in terms of Matter (fermions) and Forces (bosons). Particles of matter transfer discrete amounts of energy by exchanging bosons with...
12 December 2017 2,314 10 View
Neutrinos have mass, but the Standard Model can't easily account for how they get those masses, but the Standard Model can't easily account for how they get those masses....
10 October 2017 6,923 12 View
The Standard Model describes the phenomena within its domain accurately, it is still incomplete. Perhaps it is only a part of a bigger picture of the modern physics which includes the deeper and...
10 October 2017 8,706 18 View
Maxwell formulated dynamical theory of the electromagnetic has showed light is an electromagnetic wave. The speed c of an electromagnetic wave is determined by the constants of electricity and...
10 October 2017 9,099 90 View
Heat transfer by thermal radiation All bodies radiate energy in the form of photons moving in a random direction, with random phase and frequency. When radiated photons reach another surface, they...
02 February 2016 6,696 6 View
Einstein’s theory of gravity is very good at explaining the behavior of large objects. General relativity also gives us some insight into the nature of gravitons. In general relativity, the...
01 January 2016 464 21 View
Quantum field theory comes from starting with a theory of fields, and applying the rules of quantum mechanics. A field is simply a mathematical object that is defined by its value at every point...
01 January 2016 8,954 39 View
Planck Epoch (or Planck Era), from zero to approximately 10^-43 seconds (1 Planck Time): This is the closest that current physics can get to the absolute beginning of time, and very little can be...
12 December 2015 9,787 5 View
From the standpoint of physics, there is one essential difference between living things and inanimate clumps of carbon atoms: The former tend to be much better at capturing energy from their...
12 December 2015 9,998 1 View
The Nobel Prize in Physics 1965 was awarded jointly to Sin-Itiro Tomonaga, Julian Schwinger and Richard P. Feynman "for their fundamental work in quantum electrodynamics, with deep-ploughing...
12 December 2015 7,744 99 View
Once a photon of light is born, it travels at a speed of 300,000 km/sec until it collides with a charged particle and is diverted in another...
12 December 2015 7,216 50 View
Aephraim Steinberg of the University of Toronto in Canada and his team of researchers have performed measurements of photons and showed that the act of measuring can introduce less uncertainty...
11 November 2015 6,820 82 View
In quantum physics, a quantum fluctuation is the temporary change in the amount of energy in a point in space, as explained in Werner Heisenberg's uncertainty principle. Earlier this year, PhysOrg...
11 November 2015 3,411 21 View
The Standard Model is both remarkably simple and very powerful. There are complex equations expressing all this in a mathematical way. These equations allow theorists to make very precise...
11 November 2015 4,664 8 View
Symmetries are not hard to find. Plates in the china shop look the same when rotated; serving platters are identical to their mirror reflection. But much of the world is messy and asymmetric, and...
10 October 2015 10,053 18 View
Time moves forward because a property of the universe called "entropy," roughly defined as the level of disorder, only increases, and so there is no way to reverse a rise in entropy after it has...
08 August 2015 779 5 View
QED rests on the idea that charged particles (e.g., electrons and positrons) interact by emitting and absorbing photons, the particles that transmit electromagnetic forces. These photons are...
06 June 2015 8,501 24 View
In modern physics the terms mass and energy are often used synonymously. And force changes particle's kinetic energy. Also in thermodynamics, a force can change the internal energy of a system. In...
04 April 2015 9,787 36 View
According to quantum mechanics, the vacuum state is not truly empty but instead contains fleeting electromagnetic waves and particles that detonate into and out of existence. Also, in conventional...
01 January 2015 801 72 View
Dirac's equation defines an electron and a positron. In pair production we saw that a photon produces two charged particles, an electron and a positron with negative and positive charges. How we...
09 September 2014 597 0 View
The virtual photon's plane wave is seemingly created everywhere in space at once, and destroyed all at once. Therefore, the interaction can happen no matter how far the interacting particles are...
09 September 2014 1,310 1 View
My answer is yes. Because there are some unanswered questions or complex concepts in modern physics. The questions that modern physics does not have answers for, and the physicists believe that it...
09 September 2014 3,112 2 View
According to general relativity, the initial state of the universe, at the beginning of the Big Bang, was a singularity (with infinite density and zero volume). Both general relativity and quantum...
09 September 2014 568 1 View
Relativistic Newton second law which shows the mass variations (i.e., the infinite speed in classical mechanics is replaced by the infinite mass). Infinite mass is not observable (such as infinite...
09 September 2014 9,081 12 View
The Pound–Rebka experiment is a well-known experiment to test Albert Einstein's theory of general relativity in 1959. The result confirmed the predictions of general relativity. Proponents of the...
08 August 2014 661 33 View
Albert Einstein coined the term "Unified Field Theory," which describes any attempt to unify the fundamental forces of physics between elementary particles into a single theoretical framework....
08 August 2014 2,077 22 View
While the classical, wavelike behavior of light interference and diffraction has been easily observed in undergraduate laboratories for many years, explicit observation of the quantum nature of...
07 July 2014 2,436 4 View
The Einstein universe is one of Friedmann's solutions to Einstein's field equation for dust with density ρ, cosmological constant (Lamda), and radius of curvature Eimstein radius R(E) . It is the...
06 June 2014 4,835 2 View
Late nineteenth century physics was faced with a crisis in the speed of light and energy. Quantum characteristic of radiation was proposed by Max Planck and during the past century his theory was...
04 April 2014 2,893 11 View
Relativity theory and quantum mechanics, relying on the law of conservation of mass - energy and momentum conservation in the form of Newton's second law, are combined. Reconsideration of...
04 April 2014 4,071 1 View
Assume that the observable universe would collapse due to gravity, is there any force that can counteract with gravity collapse in the universe? In other word, after the universe collapses, how...
04 April 2014 2,513 6 View
This may probably seem an unusual question in physics however, taking it into consideration may lead us to solve some of the problems in this science. As every physicist knows, in QM and...
04 April 2014 3,498 9 View
According the theoretical physics development in the last century, if we carefully review a pair production and decay and the results of high-energy particle collisions, can we understand the...
03 March 2014 1,412 7 View
The standard way to explain this conundrum is an idea called inflation, which suggests that the universe went through a short period of rapid expansion early on – so the temperature evented out...
01 January 1970 9,838 9 View
Simple Definition of nature, the physical world and everything in it (such as plants, animals, mountains, oceans, stars, etc.) that is not made by...
01 January 1970 5,532 6 View
WE ARE born. We die. We call the span that separates these events time. Its passage is perhaps the most fundamental feature of our human experience, yet we are incapable of saying exactly what it...
01 January 1970 7,387 98 View
Do we have to take the speed limit as granted or can we explain/derive its existence from some more fundamental...
01 January 1970 8,945 46 View
"When an electron is hit by a photon of light, it absorbs the quanta of energy the photon was carrying and moves to a higher energy state. One way of thinking about this higher energy state is to...
01 January 1970 1,594 17 View
Quantum Gravity The biggest unsolved problem in fundamental physics is how gravity and the quantum will be made to coexist within the same theory. Quantum Gravity is required to make the whole of...
01 January 1970 3,507 0 View
https://www.quora.com/What-are-the-basic-elements-that-must-be-available-in-the-theory-of-everything/answer/Hossein-Javadi-1?share=7f7b7870&srid=F7rA What is a theory of everything? “A Theory...
01 January 1970 3,670 28 View
01 January 1970 381 5 View
To unify fundamental forces, of the first we need to understand and describe how are generated quantum fields. Adaptive Review of Three Fundamental Questions in...
01 January 1970 536 0 View
A photon has size but probably not in the rigid sense that we think about with macroscopic objects. Although photons exhibit properties of particles (and we know the size and mass of subatomic...
01 January 1970 1,875 3 View
Vacuum has friction after all https://www.newscientist.com/article/mg20927994-100-vacuum-has-friction-after-all/
01 January 1970 7,216 14 View
Scattering of light by matter has been studied extensively in the past. Yet, the most fundamental process, the scattering of a single photon by a single atom, is largely unexplored. One prominent...
01 January 1970 7,486 16 View
According to the theory of General Relativity, gravity isn't a force but rather the effects of objects curving space-time. Also, Einstein attempted to unify the general theory of relativity with...
01 January 1970 416 17 View
Why are anti-particles defined as particles having negative energy and propagating backward in time in solutions for the Dirac equation? Do they really have negative energy and if so, what is...
01 January 1970 7,612 3 View
In pair production and decay, energy is converted to matter (electron and positron) and vice versa. Are conservation laws only related to matter and energy (photon) is just a part of this process...
01 January 1970 7,882 31 View
01 January 1970 9,693 7 View
What is a particle? https://www.quora.com/What-is-a-particle/answer/Hossein-Javadi-1?share=b166fc35&srid=F7rA Complexity the particle and field concept in quantum mechanics has caused some...
01 January 1970 8,625 3 View
