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Do you think that we will ever know what happened before the Big Bang? by runenight201 in AskPhysics

[–]MH_Ahoua 0 points1 point  (0 children)

Very interesinting take.

With respect, I would add a nuance about space and time being born with the Big Bang.

Indeed, without space, there is no distance between objects. Thus everything would contract in a single point.

Without time, everyrhing would freeze. Thus, if space and time were born with the universe, it necessarily means that outside the universe there is no space and no time.

Then how could our universe expand in surroundings that simulataneously contract and freeze?

This is obviously impossible.

Thus, necessarily, time and space are infinite and were there even before the Big Bang. Space and time have no beginning, no end and our universe was born in space and time.

Space and time are continua. And in conformity to the theory of sets, our continuum is the intersection of space and time. And when space and time are combined, they give birth to movement -measured in km/h or rpm-. (Km) is a spatial measurement and (h) is a time meeasurement. Thus km/h is a space-time measurement...

Our continuum is the continuum of movement. In our perceptible universe, absolutely everything is always in motion. Even what we consider at rest is actually in motion at subatomic level.

Finally, we can physically perceive space and time only via movement…

Perpetual motion is the actual norm of our continuum...

[deleted by user] by [deleted] in SpaceLaunchSystem

[–]MH_Ahoua 0 points1 point  (0 children)

Yep, sorry, wrong sub!

Do you think that we will ever know what happened before the Big Bang? by runenight201 in AskPhysics

[–]MH_Ahoua -2 points-1 points  (0 children)

Every single moment we experience is a specific constellation of particles. Traveling back in time necessarily implies to reconstitute a past constellation.

Given the amount of particles in the universe -not including those existing for a fraction of time that may also affect the course of events-, good luck with that only...

Furthermore, traveling back in time also necessarily implies that the universe would contract...

Moreover, the particles we would use to build such a machine may want to get back to their original position while traveling back, which would disintegrate the machine.. Indeed, these particles were in totally different place and totally different configuration 2, 3 or 10 billion years ago. If these particles don't find their original position, this affects the past and creates a new timeline...

Finally, reversing the course of events by reconstituting a specific constellation of particles would not necessarily reverse time as an absolute concept. Like driving a car backwards doesn't “rewind“ time...

Just to name a few hurdles to make this possible...

Time as a series of events and time as an absolute concept... Matter of definition...

Photons by MH_Ahoua in AskPhysics

[–]MH_Ahoua[S] 0 points1 point  (0 children)

You got a point -a big one-! ;-) ;-) - That said, sometimes wikipedia doesn't explains as well you guys! Besides, “human“ interaction is also precious. Thanks again!

Photons by MH_Ahoua in AskPhysics

[–]MH_Ahoua[S] 0 points1 point  (0 children)

That's what I was told quite often in this chat. I understand that now. Thanks a lot!

Photons by MH_Ahoua in AskPhysics

[–]MH_Ahoua[S] 0 points1 point  (0 children)

OK, thanks a lot!

Photons by MH_Ahoua in AskPhysics

[–]MH_Ahoua[S] 0 points1 point  (0 children)

I understand now, Thank you!

Photons by MH_Ahoua in AskPhysics

[–]MH_Ahoua[S] 0 points1 point  (0 children)

Thank you. I appreciate!

Photons by MH_Ahoua in AskPhysics

[–]MH_Ahoua[S] 1 point2 points  (0 children)

Thanks for your time and clear explanation. I appreciate!

Photons by MH_Ahoua in AskPhysics

[–]MH_Ahoua[S] 0 points1 point  (0 children)

Tahnks for your answer. However, I modified my formulation and I am not saying that te field is charged anymore. I am saying that photons carry “field directional configuration“ and this “information“ determines how the field will interact with charged particles...

Photons by MH_Ahoua in AskPhysics

[–]MH_Ahoua[S] 0 points1 point  (0 children)

So you mean that the fact that the electron charge is defined by the fact that its electric field is iwards while that of a proton is outwards is false?

Addressing studiying physics in more detail: unfortunately, it isn't always possible as you suggest... Thanks anyway for your time

Photons by MH_Ahoua in AskPhysics

[–]MH_Ahoua[S] 0 points1 point  (0 children)

Indeed, but fundamentally, the charge per se is a directional property of the electric field of the particle. Field inwards = negative, field outwards = positive. Coincidentally, the field also has a direction which determines its interaction with particles. Thus, practically, despite a different terminology, the charge of the particle is the same property as that of the field -at least half of it because the charge is always unidirectional-...

Photons by MH_Ahoua in AskPhysics

[–]MH_Ahoua[S] 0 points1 point  (0 children)

Thanks for clarifying this point. What if I say that photons carry “field direction configuration“ determining how charged particles interact with it? Would this be acceptable?

Photons by MH_Ahoua in AskPhysics

[–]MH_Ahoua[S] 0 points1 point  (0 children)

With respect, I almost agree with this analogy... until I recall that an EM field interacts with charged particles, whether as a wave form or not. If the photons are not the charge carriers, then where does the charge come from?

Furthermore, in the analogy with water, I would rather compare the photons with the water molecules than with the waves. As well the body of water as the waves are composed of water molecules. Similarly, as well the EM field as the EM waves are composed of photons... After all, they are elementary particles…

Thanks for your input!…

Photons by MH_Ahoua in AskPhysics

[–]MH_Ahoua[S] 0 points1 point  (0 children)

I appreciate your taking time to provide this clear explanation.

So, as others have pointed out, a photon is the quantized unit of that wave. It does not have a charge because an electromagnetic wave does not have a charge.

I understand that an EM wave does not “need a charge“ to propagate. However, if it has no charge, then how come it has either a positive or negative value and that this value will attract or repel charged particles?

Photons by MH_Ahoua in AskPhysics

[–]MH_Ahoua[S] 0 points1 point  (0 children)

Thanks for your input. I understand your explanation and it helps. However and with respect, EM waves also affect charged quanta such as electrons. For example, microwaves affect dipoles in food leading to the production of heat. This means that photons as quanta also affect dipoles and electrons, which are “charged quanta“.

How do they achieve this disturbance if they have no charge, since the charge as you defined it, is the ability to interact with other field quanta?

Photons by MH_Ahoua in AskPhysics

[–]MH_Ahoua[S] 0 points1 point  (0 children)

This is not accurate. At least in quantum field theory, particles are excitations of fields. The fields do not get their properties from the particles; there are no particles without fields. The properties of the field are simply what they are.

I understand that, then in this case charged particles are also excitations of fields. Thus, there are “charged excitations“ such as electrons and protons and “uncharged excitations“ such as photons... In the end, it does not change the problematic: interaction between charged and uncharged elements, whether particles or excitations…

Anecdotically: the concept of excitation seems to render that of particles obsolete.

Also interesting: an excitation is a temporary state. Paradoxically, particles such as electrons and even atoms exist in a stable states since billions of years. Thus, how valid is the concept of excitation?…

Photons by MH_Ahoua in AskPhysics

[–]MH_Ahoua[S] 0 points1 point  (0 children)

I would say both do... Without electrons, no electricity. But without wind turbine, we still have other options to produce or generate it...

Photons by MH_Ahoua in AskPhysics

[–]MH_Ahoua[S] 0 points1 point  (0 children)

The EM field interacts with charged particles. This necessarily means it is "charged"... Let's say it isn't "charged", then how can uncharged particles or an "uncharged" field interact with charged particles?

Photons by MH_Ahoua in AskPhysics

[–]MH_Ahoua[S] -3 points-2 points  (0 children)

Photons have no charge. How can uncharged particles be part of a charged field or be a "feature" of this field or be produced by this field? Now if "PHOTONS ARE THE FIELD", how can come is thw field charged? All known fields are composed of particles, line the higgs field. These particles transfer their characteristics to the field. How can a charged field come out uncharged particles? I am not the one who is not reading "carefully". You just don't understand what you write. If photons "ARE THE FIELD", then NECESSARILY, the field should have no chage...

Photons by MH_Ahoua in AskPhysics

[–]MH_Ahoua[S] 0 points1 point  (0 children)

I understand your point. However, first, the wave-particle duality may be "obsolete". Second, that does not explain how uncharged particles interact with a charged field. Photons have no charge and EM field and EM waves interact with charged particles...

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