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Physics, Astronomy & Cosmology / Re: Can gravity be said to act in two opposite directions at once ?

« on: 21/10/2018 12:23:23 »

The gravitational field around an object is three dimensional. As Bored Chemist has explained quite succinctly. If we define spheres around the earth of increasing radius we would find that the force of gravity diminishes with increasing distance from the earth. The sun is so much further away from the earth than the moon that it's overall influence is diminished. This is determined mathematically as others have demonstrated here and elsewhere in other topics. It is worthwhile to pick up some books on the subject. Expand your mind!

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Physics, Astronomy & Cosmology / Re: Is the universe expanding faster than the speed of light?

« on: 25/09/2018 02:15:18 »

If objects with non zero rest mass cannot travel faster than light then this means that gravity itself cannot make them travel faster than light. We are embedded in a universe with an enormous amount of matter surrounding us. All this matter generates gravitational fields. Our view of time is therefore not absolute. Which means our view of speed is not absolute. That is the first point. The second point is what is space? How do we reconcile speed through the vacuum. We can't use a measuring device, since we cannot be considered stationary with respect to anything other than our own 'inertial' frame. Especially not with respect to a vacuum. Therefore we can only determine speed via the shift in frequency of incoming signals. If you have no absolutely stationary markers to go by then signals is all you have. You then determine what you think is the distance and also the speed of an object by interpreting those signals. Since the shifting is pretty consistent it can be taken to show an expanding universe.

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Physics, Astronomy & Cosmology / Re: Does gravity have an infinite range?

« on: 21/09/2018 13:48:55 »

@evan_au This may help with an understanding of the combination of forces.
http://hyperphysics.phy-astr.gsu.edu/hbase/Astro/unify.html

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New Theories / Re: What are they saying about Quantum Gravity?

« on: 20/09/2018 19:03:28 »

If you want to brush up on virtual particles then read this article by Matt Strassler.
Virtual Particles:What are they?

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Physics, Astronomy & Cosmology / Re: What do strange quarks do?

« on: 12/09/2018 17:58:22 »

Outside the nucleus, free protons are considered stable while free neutrons are not. The decay involves flavor change. That is the flavor change from down to up for one of the quarks in the neutron. This flavor change is via the weak nuclear force and results in the change of the neutron to a proton. This involves the emission of a W^- boson. This boson then decays to an electron and an antineutrino. We also find flavour change in neutrinos. This is neutrino oscillation, which is similar to color change among quarks. In that both are 'oscillations'. What causes the neutron to be stable within the nucleus and unstable outside is very interesting. The majority of composite particles are short lived in the current era of the universe.

See also the neutron lifetime puzzle.
https://en.wikipedia.org/wiki/Free_neutron_decay

EDIT: On the neutron lifetime puzzle.
https://www.quantamagazine.org/neutron-lifetime-puzzle-deepens-but-no-dark-matter-seen-20180213/

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Physics, Astronomy & Cosmology / Re: How can a universe start from nothing?

« on: 29/08/2018 13:11:02 »

Macro level objects not only absorb wave energy in quantum increments based on their quantized content which governs the frequency of inflowing wave energy that they can absorb, but macro level objects also emit gravitational wave energy in quantum increments.

I would disagree with you here on various levels, but keeping it simple for a particle to radiate gravitational energy it would be losing energy and eventually disappear. Particles can not radiate or absorb gravitational energy, without gaining or losing mass/energy. It goes against the laws of physics and the conservation of energy. Verlindes theories suggest the entanglement of space is absorbed around mass/energy, reducing the entropy of space, which again is a bit of a violation to reduce entropy, but no one seems to have jumped on his ideas and said he cant reduce the entropy around mass/energy and his ideas seem close to gaining acceptance, and they do support the MOND curvefit with actual theoretical physics.

How would anyone define negative and positive energies for a zero energy universe. Matter and antimatter do not cancel out, they produce radiation when they come into contact. When space meets mass it appears to curve, possibly as a result of the reduction of entanglement entropy, similar to a black hole, which might be connected to the rest of space via a wormhole ??

What about electromagnetic radiation? The particles should disappear in this case too if your idea had any merit.

Accelerating objects radiate.

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Physics, Astronomy & Cosmology / Re: False Vacuum; Who, What, Where, When, Why?

« on: 15/08/2018 14:32:09 »

An article of interest.
http://scholar.google.co.uk/scholar_url?url=https://arxiv.org/pdf/gr-qc/0503090&hl=en&sa=X&scisig=AAGBfm3pHMd7HXOHV_J1Or6sk-apZBGrWg&nossl=1&oi=scholarr

28

Geek Speak / Re: Victim of an Adult Site Blackmail Email Hoax?

« on: 14/08/2018 21:57:51 »

They probably have small members and feel inadequate. They need the blackmail money for their new 'extension'.

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Physics, Astronomy & Cosmology / Re: False Vacuum; Who, What, Where, When, Why?

« on: 31/07/2018 21:19:08 »

The Higgs field would have to be tuned precisely to the value of the false vacuum for it not to have a detectable effect upon it. See the following.
https://profmattstrassler.com/articles-and-posts/particle-physics-basics/how-the-higgs-field-works-with-math/2-why-the-higgs-field-is-non-zero-on-average/

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Physics, Astronomy & Cosmology / Re: False Vacuum; Who, What, Where, When, Why?

« on: 23/07/2018 19:36:25 »

It may also be pertinent to read about the possibility of electron decay and just how likely that is. This also brings up the issue of violation of charge conservation. https://physics.aps.org/synopsis-for/10.1103/PhysRevLett.115.231802

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Physics, Astronomy & Cosmology / Re: False Vacuum; Who, What, Where, When, Why?

« on: 23/07/2018 19:26:18 »

Investigate a question. How long will it take for a proton to decay. https://en.wikipedia.org/wiki/Proton_decay The proton may never decay or it may just be a very long time before it does. It is a question of stability. In the case of a false vacuum the stability arises from the idea that there is a 'hill' between the false and true vacuum potentials. In the same way there are barriers to proton decay. See especially:

"According to the Standard Model, protons, a type of baryon, are stable because baryon number (quark number) is conserved (under normal circumstances; see chiral anomaly for exception). Therefore, protons will not decay into other particles on their own, because they are the lightest (and therefore least energetic) baryon. Positron emission – a form of radioactive decay which sees a proton become a neutron – is not proton decay, since the proton interacts with other particles within the atom."

32

General Science / Re: Is zero an even number, odd number, or neither?

« on: 22/07/2018 09:41:09 »

0/1, and the related infinity

I think you mean "1/0, and the related infinity".

A lot of mathematicians survived over the centuries without accepting that zero was a real number, even if they accepted "0" as a placeholder in Indian/Arabic numerals.

I believe what was meant was 0/1 and the related 1/0 infinity. The idea of zero being divided by anything else is a strange one when contemplated.

33

Physics, Astronomy & Cosmology / Re: How real is (my understanding of) the Copenhagen Interpretation?

« on: 05/07/2018 07:34:12 »

The biggest problem is that the measuring device cannot be independent of the object that it is measuring. It affects the object it is measuring.

Undoubtedly; but it doesn't say how one could aim at, or hit, an object that doesn't exist until it is hit.

Well then, the object has to exist. An indeterminacy relates more to our lack of understanding than to whether or not a particle exists. Quantum mechanics is a model. It approximates an underlying reality. We are taught to believe what our senses tell us but they are fallible.

34

Physics, Astronomy & Cosmology / Re: How is it possible for the Sun to set in the northwest?

« on: 26/06/2018 12:26:18 »

This depends upon the position of the ecliptic. This is generally the path that planets and the sun take around the sky from our point of view. Also the coastline at Whitby is slanted north westwards.

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Physics, Astronomy & Cosmology / Re: Is there a difference between zero energy and a zero balance of energy?

« on: 25/06/2018 06:28:42 »

Are you thinking of transformations Bill?

No. I'm thinking: is there a difference between no energy and two lots of energy, each of which cancels  out the other, but both of which remain. 

  The question to ask is what was the energy balance during this process and how does it relate to the current state of the universe?

OK, so I asked the wrong question!  Does this mean that no one knows the answer to my question; there is no answer to my question; or, my question is so silly, it makes no sense to anyone other than me?

No it wasn't the wrong question at all. I just extended it. There can never be just zero energy. Otherwise nothing exists. The energies can balance out. Imagine an object at its apex of a trajectory upwards in a gravitational field. The kinetic and potential energies balance. This does not mean that the energy of the object is gone. It still has rest energy.

36

Physics, Astronomy & Cosmology / Re: Efficiency of light as energy source?

« on: 22/06/2018 19:17:35 »

Photons are defined in terms of energy, E = hf. Here h is Planck's constant and f is the frequency of light. Since frequency is variable then any equivalent mass that can be defined for the photon also changes. This cannot be defined as rest mass and therefore must depend entirely upon kinetic energy. In terms of objects with rest mass, kinetic energy is connected to a change in velocity and not to any change in frequency. The energy changes for entirely different reasons. This is like comparing apples and pears.

37

Plant Sciences, Zoology & Evolution / Re: Can a plant recognize someone looking into his direction?

« on: 20/06/2018 12:24:43 »

The more we learn about the communication skills of other species the less arrogant we should become as a species. However, we are nowhere near smart enough to appreciate the implications.

38

Physics, Astronomy & Cosmology / Re: Can time emerge?

« on: 12/06/2018 19:06:19 »

If you want to take this further then it might be instructive to browse the following article. Where ER=EPR.
https://www.sciencenews.org/blog/context/new-einstein-equation-wormholes-quantum-gravity

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Physics, Astronomy & Cosmology / Re: Can time emerge?

« on: 12/06/2018 12:28:10 »

Wheeler deWitt and the emergence of time.
https://medium.com/the-physics-arxiv-blog/quantum-experiment-shows-how-time-emerges-from-entanglement-d5d3dc850933
An interesting read and not that long.

40

Physics, Astronomy & Cosmology / Re: What started the Big Bang?

« on: 02/06/2018 14:23:03 »

If you consider the collapse of a false vacuum (speculative), it will propagate outward at the speed of light. In a similar way, the effect of quantum fluctuations on a condensate would also propagate outward at the speed of light. If a quark gluon plasma can be thought of as a condensate then the big expansion can have a point of origin. I doubt it involved any kind of bang that we would recognize.