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  2. Profile of jeffreyH
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Messages - jeffreyH

Pages: [1] 2 3 ... 311
1
Physics, Astronomy & Cosmology / Re: How fundamental is time?
« on: Yesterday at 22:26:57 »
I think at this point it is worth waiting to see what a cosmologist thinks.

2
Physics, Astronomy & Cosmology / Re: Is all motion relative?
« on: Yesterday at 21:45:41 »
Considering relative things and acceleration the two can be combined to find the relative time dilation of an accelerating object using T = T0/√(1 -[2as]/c2). Where a is acceleration and s is the distance traveled.

3
The Environment / Re: Are insect species dying out?
« on: Yesterday at 15:23:48 »
Unless the habits and lifestyles of 7 billion people can be changed very quickly I think it's curtains for us. Looking at the nonsense schoolyard political games currently being played out I think our fate is sealed

4
Physics, Astronomy & Cosmology / Re: What field gives rise to the Van Der Waals forces?
« on: 16/02/2019 14:41:41 »
Is this simply a description of quantum fluctuations in the field? See here https://en.m.wikipedia.org/wiki/Quantization_of_the_electromagnetic_field under second quantisation.

5
Physics, Astronomy & Cosmology / Re: What field gives rise to the Van Der Waals forces?
« on: 16/02/2019 14:36:00 »
Apart from the following on the Wikipedia page on the Casimir effect.
"The Casimir effect can be understood by the idea that the presence of conducting metals and dielectrics alters the vacuum expectation value of the energy of the second quantized electromagnetic field. Since the value of this energy depends on the shapes and positions of the conductors and dielectrics, the Casimir effect manifests itself as a force between such objects."
https://en.m.wikipedia.org/wiki/Casimir_effect
So what is the second quantised electromagnetic field?

6
Physics, Astronomy & Cosmology / Re: What field gives rise to the Van Der Waals forces?
« on: 16/02/2019 14:28:57 »
On the Wikipedia page it states "The van der Waals force has the same origin as the Casimir effect, arising from quantum interactions with the zero-point field." I am not sure how this would relate to the electromagnetic field.

7
The Environment / Are insect species dying out?
« on: 16/02/2019 08:27:03 »
Studies appear to show a worrying decline in many insect species. Is this a far more existential threat than any change in climate?
https://www.google.com/amp/s/relay.nationalgeographic.com/proxy/distribution/public/amp/animals/2019/02/why-insect-populations-are-plummeting-and-why-it-matters

8
General Science / Re: Can you compare infinites?
« on: 16/02/2019 07:59:10 »
This all involves number theory and pure mathematics. Very interesting subjecs with more puzzles than just infinity. Take, for instance the Riemann zeta function.
https://en.m.wikipedia.org/wiki/Riemann_zeta_function
Or Euler's identity.
https://en.m.wikipedia.org/wiki/Euler's_identity

9
Physics, Astronomy & Cosmology / What field gives rise to the Van Der Waals forces?
« on: 16/02/2019 07:27:49 »
Since forces can be associated with fields I am wondering what this one is.

10
Physics, Astronomy & Cosmology / Re: How do we measure the energy of a photon?
« on: 14/02/2019 18:45:28 »
@esquire Garbage in garbage out. You dump garbage in the forum, we can always bin it for you. You have been given various correct answers which you simply won't accept. The moderators here are all volunteers. They have better things to do than put your toys back in the pram. Please try harder to be a valued member. You never know you may learn enough to help others.

11
Physics, Astronomy & Cosmology / Re: How fundamental is time?
« on: 12/02/2019 21:12:48 »
Quote from: chiralSPO on 12/02/2019 21:01:21
Quote from: yor_on on 12/02/2019 05:55:38
'c' is a variable in that it is is observer dependent.

My understanding is that this is not the case. The theories of special and general relativity are built around the concept that all observers agree on c, no matter what reference frame they are in...

Yes. Time dilation depends upon the value of c. Otherwise we would still be using Galilean relativity.

12
New Theories / Re: Is my Theory Of Gravitational Field valid?
« on: 12/02/2019 21:07:16 »
The gravity of the dilemma eludes the scribe.

13
Physics, Astronomy & Cosmology / Re: How fundamental is time?
« on: 11/02/2019 22:56:10 »
Quote from: yor_on on 11/02/2019 22:12:19
I'm wondering Chiral. This is collected thoughts on 'c' as a variable. http://www.ldolphin.org/cdkconseq.html

with a time dilation you could argue that 'c' changes too, from the 'eyes of a God' so to speak. See if you can find something interesting :)

Your link is likely related to creationism and therefore of dubious value. Constants are named so because they do not change. Unless they want to convince everyone the earth is only 6000 years old.

14
Physics, Astronomy & Cosmology / Re: How fundamental is time?
« on: 10/02/2019 16:34:53 »
Absolutes in physics tend to be out of reach. Massive particles reaching the speed of light or temperature being lowered to absolute zero come to mind. It should be the same with an absolute frame of reference.

15
Physics, Astronomy & Cosmology / Re: How fundamental is time?
« on: 07/02/2019 12:44:13 »
You can map your function onto a spacetime diagram. As α converges with t there is a connection to the speed of light. The function approaches a light-like path. This will only match at α = ∞. This may be the connection to both time dilation and a fundamental time scale.

EDIT: It seems to me that the green line functions are closer to a match with inflation. That is if you take the connection with spacetime diagrams into consideration.

That way you don't affect the accelerating expansion idea. When α = 0 this could be like a Planck scale equivalent. Before that we are barred from knowing anything. This would be the big bang initiation. Then inflation which quickly converges α and t.

16
Physics, Astronomy & Cosmology / Re: How fundamental is time?
« on: 06/02/2019 23:22:49 »
How would the relationship between α and t relate to time dilation? Would α at negative infinity relate somehow to zero point energy?

17
General Science / Re: Why does our solar system resemble the structure of an atom?
« on: 04/02/2019 18:27:07 »
Pluto would then be an outlier.

18
Physics, Astronomy & Cosmology / Re: Does structural integrity vary proportionately with relativistic mass?
« on: 03/02/2019 16:03:16 »
Quote from: alancalverd on 02/02/2019 22:22:17
Quote from: jeffreyH on 02/02/2019 12:34:17
The nearer an object's velocity gets to the speed of light, the effects will start to resemble the tidal forces on an object approaching a black hole. Since the forces holding the object together themselves travel at light speed this has to be the case. Otherwise relativity breaks down.

Quote
Reported in November 1994 in Monthly Notices of the Royal Astronomical Society is a galaxy with a measured red shift of z=4.25 , a new record. This value for the z parameter corresponds to a recession speed of .93c
. but I haven't noticed any change in my structural integrity.


It all depends upon whether or not you consider the space between the galaxies to be expanding without affecting other processes. For instance, at that recessional velocity time dilation would start to have dramatic effects upon our ability to accurately determine velocities. What we would measure would be .93c but is it accurate?

19
Physics, Astronomy & Cosmology / Re: How fundamental is time?
« on: 02/02/2019 22:14:40 »
Have you tried plotting the function? What does it look like?

20
Physics, Astronomy & Cosmology / Re: Does structural integrity vary proportionately with relativistic mass?
« on: 02/02/2019 21:23:58 »
The structural integrity of ice is disrupted by increasing its temperature. This disrupts the molecular bonding. The kinetic energy introduced to the system overcomes the bonding. The structural integrity of the molecules remains intact. Forces, that introduce stresses and strains, disrupt structural integrity. This obviously includes acceleration. However, relativistic mass does not require acceleration. It is a function of relative velocity. So the structural integrity in this case is simply a function of velocity. We can relate this velocity directly to kinetic energy.

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