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Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: thebrain13 on 01/11/2007 01:50:03

Title: Are electrons affected by gravity?
Post by: thebrain13 on 01/11/2007 01:50:03
how do we know that gravity affects electrons? We cant build anything exclusively out of electrons, and if we do isolate them, we have to keep them there using something made partly from protons.(right?) Can we actually ever get electrons by themselves? how do we know that gravity doesnt just affect positive mass, and the much larger positive mass is just dragging the much smaller negative mass along?
Title: gravity and electrons
Post by: DoctorBeaver on 01/11/2007 14:08:29
Electrons have such little mass that gravity has a negligible effect on them. To put it in perspective, in a hydrogen atom the gravitational force between the electron and the proton is approximately 10-43 times smaller than the electrical force.
Title: gravity and electrons
Post by: lyner on 01/11/2007 14:26:51
Quote
Electrons have such little mass that gravity has a negligible effect on them
It's more a matter of e/m than just m. (The ratio of charge to mass).
It's interesting to calculate the electric force between two standard units of charge (coulomb) separated by the standard unit of length (metre), then to do the same thing, working out the gravitational force  between two masses (kg ) separated by one metre.
One so huge and one so small.

 I notice , brain13,  you are talking of positive and negative masses - both have positive mass - it's the charges that have different signs.

But electrons certainly do exhibit and possess momentum - therefore, because they are not traveling at c, they must have mass. So, unless there is something wierd about them, they will have weight, too.
Title: gravity and electrons
Post by: thebrain13 on 01/11/2007 15:54:28
I didnt mean to say that electrons have mass that is less than zero, or negative mass, as your thinking of it. I meant the mass it does have is negatively charged, and was wondering how do we know that negatively charged mass is affected by gravity the same way that positively charged mass is.
Title: gravity and electrons
Post by: Mr Andrew on 01/11/2007 22:46:53
Charge and mass are totally seperate.  Gravity only affects mass...Electricity only affects charge.
Title: gravity and electrons
Post by: thebrain13 on 01/11/2007 23:26:07
Right, Im asking, how do we know that.
Title: gravity and electrons
Post by: thebrain13 on 05/11/2007 22:37:15
In other words im asking, what experiment shows that gravity affects electrons?

Not what theory says gravity affects electrons.
Title: gravity and electrons
Post by: Mr Andrew on 06/11/2007 02:09:30
If electrons weren't affected by gravity then a cathode ray would be bent due to the earth spinning and moving through space all of that (Newton's First Law).  It isn't.
Title: gravity and electrons
Post by: thebrain13 on 06/11/2007 02:49:37
As short as that explanation is, I dont understand what you are trying to say.
Title: gravity and electrons
Post by: JP on 06/11/2007 18:09:48
how do we know that gravity doesnt just affect positive mass, and the much larger positive mass is just dragging the much smaller negative mass along?

I'm interpreting you as meaning "What if gravity only affects protons and neutrons, and this accounts for the gravitational mass of matter?"

I don't think there is an experiment that shows electrons are affected by gravity.  As DoctorBeaver said, electrons have such a small mass, and electromagnetic forces are so large compared to gravity, that gravity gets swamped out by electromagnetism when looking at electrons.  However, we do know that electrons have inertial mass (the mass that requires you to put in energy in order to accelerate them), as sophiecentaur mentioned.  It's generally accepted that inertial mass and gravitational mass are equivalent, though actually demonstrating this experimentally at the quantum level is difficult (again, due to gravity being so tiny compared to other quantum-level forces).  More importantly, there's no good reason to assume that electrons aren't affected by gravity: everything we're able to measure is affected by gravity regardless of its charge, so why should it be different for electrons?
Title: gravity and electrons
Post by: Soul Surfer on 06/11/2007 18:13:37
Mr Andrew that looks like a load of tripe.

It is quite easy in theory to show that electrons respond to gravity.

Electrons like everything else will fall with the acceleration of gravity like a shot from a gun so if you shoot a beam horizontally so if you set up a fine beam of electrons running a long distace horizontally through a small hole and then turn the electron beam apparatus upside down the electrons will miss the hole because the gravity causes the beam to bend in the other direction.  Any residual electric or magnetic field effects will be identical only the gravitiatinal effect will change.

In practice this experiment is quite difficult to carry out and I'm not sure if it has actually been done. but gravitational effects on subatomic particles have to be allowed for in certain critical precise experimentation
Title: gravity and electrons
Post by: syhprum on 06/11/2007 19:54:53
I can not remember the exact details but there was a famous experiment to determine the e/m ratio where charged tiny oil drops were observed falling and the amount of charge varied until the lowest rate of fall was observed

Sorry muddled thinking !

It is generally agreed that the electron has a mass of 1/1836 that of the proton and like all objects with mass is subject to gravitational attraction
Title: gravity and electrons
Post by: JP on 06/11/2007 20:39:45
That's the experiment [Millikan's oil drop experiment] I thought of first, syphrum.  However, the gravitational force in this experiment is due to the mass of the entire oil drop, and the electron mass is a negligible contribution to it.
Title: gravity and electrons
Post by: chrisdsn on 06/11/2007 23:23:55
You can work out the ratio of the mass of the electron to it's charge
by measuring the deflection of a beam of electrons in a magnetic field.

http://phoenix.phys.clemson.edu/labs/cupol/eoverm/index.html

The aforementioned Millikan's oil drop will tell you the charge
of an electron (kinda: it's very hard to do right; even Millikan
got it a little wrong). Combine the two and you get the mass.   
Title: gravity and electrons
Post by: syhprum on 07/11/2007 22:26:42
When an electron meets a positron and there is mutual annihilation with the emission of a .511 Mev gamma photon does this not give you the electrons mass by the familiar e=mc^2 formula.
Title: gravity and electrons
Post by: lightarrow on 08/11/2007 13:32:08
how do we know that gravity affects electrons? We cant build anything exclusively out of electrons, and if we do isolate them, we have to keep them there using something made partly from protons.(right?) Can we actually ever get electrons by themselves? how do we know that gravity doesnt just affect positive mass, and the much larger positive mass is just dragging the much smaller negative mass along?
I've just turned of 90° the CRT Monitor of my computer: the image is slightly changed (luminosity and colours).
This means that gravity DO affect electrons!
Simple, isnt'it?
Title: gravity and electrons
Post by: JP on 08/11/2007 16:20:38
how do we know that gravity affects electrons? We cant build anything exclusively out of electrons, and if we do isolate them, we have to keep them there using something made partly from protons.(right?) Can we actually ever get electrons by themselves? how do we know that gravity doesnt just affect positive mass, and the much larger positive mass is just dragging the much smaller negative mass along?
I've just turned of 90° the CRT Monitor of my computer: the image is slightly changed (luminosity and colours).
This means that gravity DO affect electrons!
Simple, isnt'it?

That's almost certainly due to the electron beam being affected by the Earth's magnetic field.  The magnetic field-electron interaction force should be much larger than the gravity-electron interaction.  If you could eliminate the magnetic effects, then this experiment would work, but given the tiny gravitational force, it's probably not a realizable experiment at the moment. 

Everything being proposed here is good for determining the inertial mass of an electron, but I'm pretty convinced that we just don't have the technology to measure whether this is also gravitational mass: i.e. "does gravity affect electrons the same as larger objects?"  Of course, there's no good reason that I know of to assume that it doesn't, and plenty of good reasons to assume that it does. 
Title: gravity and electrons
Post by: syhprum on 08/11/2007 17:25:32
When matter orbits a black hole it is heated to such a degree that it is completely ionised, if the gravitational effect was different between Electron and Protons would this not show up in the spectrum of the electromagnetic radiation produced
Title: gravity and electrons
Post by: lightarrow on 08/11/2007 18:13:14
how do we know that gravity affects electrons? We cant build anything exclusively out of electrons, and if we do isolate them, we have to keep them there using something made partly from protons.(right?) Can we actually ever get electrons by themselves? how do we know that gravity doesnt just affect positive mass, and the much larger positive mass is just dragging the much smaller negative mass along?
I've just turned of 90° the CRT Monitor of my computer: the image is slightly changed (luminosity and colours).
This means that gravity DO affect electrons!
Simple, isnt'it?

That's almost certainly due to the electron beam being affected by the Earth's magnetic field.  The magnetic field-electron interaction force should be much larger than the gravity-electron interaction.  If you could eliminate the magnetic effects, then this experiment would work, but given the tiny gravitational force, it's probably not a realizable experiment at the moment. 

Everything being proposed here is good for determining the inertial mass of an electron, but I'm pretty convinced that we just don't have the technology to measure whether this is also gravitational mass: i.e. "does gravity affect electrons the same as larger objects?"  Of course, there's no good reason that I know of to assume that it doesn't, and plenty of good reasons to assume that it does. 
Yes, you're right. My mistake.
Title: gravity and electrons
Post by: thebrain13 on 08/11/2007 18:48:18
If you could show that electrons responded in the opposite way to gravity than protons do, that would be a big step in unifying gravity and electromagnetism. Dont ya think?
Title: gravity and electrons
Post by: lyner on 08/11/2007 19:04:23
There are many occasions when a heavy negative ion will exhibit it mass / weight so what would be so special about negative charge in that case?
Even the drops in the Millican oil drop experiment can be negatively charged. They  don't  appear to behave differently. Why would you want them to?
Conversly, positrons (positive charged particles with the same mass as the electron) exist. They don't last long but would you expect them to behave differently to electrons as regards their mass. whilst they do exist?
'If' you could show an effect it would be good but, with all these  'it would be nice if' statements, you need experimental evidence to take it any further.
The problem is that electronic forces are so much stronger than gravitational ones.
Title: gravity and electrons
Post by: syhprum on 08/11/2007 19:23:42
"positrons (positive charged particles with the same mass as the electron) exist. They don't last long"
Is there any reason to suppose that Positrons have any different life than Electrons?.
Of course when they come in contact with Electrons there is mutual annihilation but on those grounds we could say Electons have a short life!
Title: gravity and electrons
Post by: thebrain13 on 08/11/2007 19:43:45
Im not saying negatively charged ions fall up. I would predict the opposite. Because negative ions have protons in them, and the mass of the proton is way bigger than the electons, thus it should behave (almost) the same as if it was just a proton by itself.
Title: gravity and electrons
Post by: Mr Andrew on 08/11/2007 23:00:08
I'm sorry, I mistyped...the cathode ray is bent, not straight, just like the path of a bullet is bent towards the earth (which is affected by gravity).  This would imply that electrons are affected by gravity also.  One experiment would be to take a negative ion and measure its momentum in a collision and, if you know its velocity, you can calculate its mass.  Comparing this mass to the mass derived from weight would tell you if there was an 'anti-gravity' acting on the electrons in the ion (if it was larger calculated with momentum than with weight then there must be some other force acting on it).  Was that clear?
Title: gravity and electrons
Post by: lyner on 09/11/2007 00:00:01
Are you proposing that it is the negativity of the charge that makes it, somehow, different, gravitationally? What would be the effect on a positron, in a similar experiment? Why choose the negative charged particle (the chosen sign is totally arbitrary, remember) to be the one which would have a 'negative' gravitational influence?
Title: gravity and electrons
Post by: JP on 09/11/2007 17:51:07
There's probably some cosmological reason for believing that gravity affects electrons the same as it does all positively charged and neutral matter.  If electrons were repelled by gravity, then they would be slightly pushed away from all clumps of matter (such as our galaxy) by gravity, while protons and neutrons etc.  This would probably have some measurable consequences in deviation from Newtonian gravity or general relativity, which I don't think have been observed. 

There is some thought that antimatter might be affected by "negative gravity": http://en.wikipedia.org/wiki/Gravitational_interaction_of_antimatter
This might help to explain why there seems to be so little of it in the universe, but this is not a widely accepted view.
Title: gravity and electrons
Post by: lyner on 09/11/2007 22:04:10
You would need an experiment or observational evidence to take this further. Else it's idle chit chat. (Fun though)
Title: gravity and electrons
Post by: Soul Surfer on 10/11/2007 08:07:04
The universe just would not work as it does now if electrons responded to gravity differently to protons that's the plain and simple truth.  After the "dark ages"  when the universe consisted mostly of neutral atoms the universe was reionised into a plasma by the first stars it was at that time starting to form major condensations.  If the protons and electrons had at thast time moved in any way differently in the gravitiational field the universe would have developed a charge structure that opposed gravity and prevented objects from condensinf properly into stars and galaxies.  remebe it would only require a small differentiation between the motions of protons and electrons in a gravitiatinal field to crerate very large balancing electrostatic forces over the same range as gravity.

As an aside it is looking like electromagnetic forces did have an effect on the formation of galaxies and that is only just starting to be understood.
Title: gravity and electrons
Post by: thebrain13 on 14/11/2007 07:40:26
but  electric force is still way stronger than gravity. Protons are still attracted to electrons. The tendency for positive charge to coagulate would only be as strong as gravity is compared to electric force.

I dont really see how it could make a big difference.
Title: Re: gravity and electrons
Post by: ManasviMittal on 10/10/2015 11:15:37
Van der waals theory says that there is negligible effect of gravity on an electron.
On the other hand, theory of relativity tell us that gravity can effect even light particles. As it happens in a singularity, even light is not able to escape from it. So according to me, i think that gravity effects electrons on a large scale. Now, if electron uses its energy to overcome the effect of gravity, then over a certain period of time and electron should loose all its energy and should fall on the ground due to gravity.
tell me if i'm wrong.
Title: Re: gravity and electrons
Post by: alancalverd on 10/10/2015 11:26:32
Gravity has exactly the same effect on electrons as it does on any other object with mass, from an electron to a galaxy.
Title: Re: Are electrons affected by gravity?
Post by: lightarrow on 10/10/2015 14:16:21
Van der waals theory says that there is negligible effect of gravity on an electron.
On the other hand, theory of relativity tell us that gravity can effect even light particles. As it happens in a singularity, even light is not able to escape from it. So according to me, i think that gravity effects electrons on a large scale. Now, if electron uses its energy to overcome the effect of gravity, then over a certain period of time and electron should loose all its energy and should fall on the ground due to gravity.
tell me if i'm wrong.
You're wrong.

--
lightarrow
Title: Re: gravity and electrons
Post by: Colin2B on 10/10/2015 14:26:51
.... if electron uses its energy to overcome the effect of gravity, then over a certain period of time and electron should loose all its energy and should fall on the ground due to gravity.
tell me if i'm wrong.
If the electron is moving against gravity it will not lose energy, but the energy will be converted, firstly to potential energy and then as it falls into kinetic energy in the opposite direction.
This would work in a vacuum but in air the range of an electron is usually less than 2m.
Title: Re: Are electrons affected by gravity?
Post by: ManasviMittal on 10/10/2015 14:28:53
Van der waals theory says that there is negligible effect of gravity on an electron.
On the other hand, theory of relativity tell us that gravity can effect even light particles. As it happens in a singularity, even light is not able to escape from it. So according to me, i think that gravity effects electrons on a large scale. Now, if electron uses its energy to overcome the effect of gravity, then over a certain period of time and electron should loose all its energy and should fall on the ground due to gravity.
tell me if i'm wrong.
You're wrong.

--
lightarrow


How am I wrong?
Title: Re: Are electrons affected by gravity?
Post by: guest39538 on 10/10/2015 14:40:52
If electrons are influenced by gravitational force, then how is the Earth able to emit a magnetic field?



http://www.nasa.gov/feature/goddard/nasa-measuring-the-pulsating-aurora
Title: Re: Are electrons affected by gravity?
Post by: jeffreyH on 10/10/2015 17:08:23
The form of the energy taken from the electron is kinetic energy. Kinetic energy and the wavelike nature of the electron are closely related. Because of this wavelike nature the electron can never be at rest on the ground. Unless it happens to be part of a static electric charge. However an electron as part of a molecule which makes up a solid CAN rest on the ground. If it is simply a gas molecule then it is less likely to remain at rest. There is something about the wavelike nature of the gas molecule that prevents this. What that something is I don't know. For solids the wave is not free to move in a straight line path. the waveform of particles in a solid are linked together within atoms and molecules which prevents this from happening. Unless of course some external force is applied.
Title: Re: Are electrons affected by gravity?
Post by: lightarrow on 10/10/2015 20:28:02
How am I wrong?
Totally  [:)]
A longer answer would require to write an entire encyclopedia.
Write one single statement at a time, at least.

--
lightarrow
Title: Re: Are electrons affected by gravity?
Post by: MolonLabe on 11/10/2015 11:00:33
  However an electron as part of a molecule which makes up a solid CAN rest on the ground.

Please set me right here, but I understood that electrons bound to molecules in a solid were in some kind of constant state of motion around the nucleii. I know that the analogy of planets orbiting a sun is far too primitive, but I find it hard to imagine how any such electron could be described as at rest.
Title: Re: Are electrons affected by gravity?
Post by: evan_au on 11/10/2015 11:21:27
Quote from: ManasviMittal
Van der waals theory says that there is negligible effect of gravity on an electron.
Please describe which one of Van der Waals' (http://en.wikipedia.org/wiki/Johannes_Diderik_van_der_Waals) theories imply this (and why)?
Title: Re: Are electrons affected by gravity?
Post by: alancalverd on 11/10/2015 11:42:59
I know that the analogy of planets orbiting a sun is far too primitive, but I find it hard to imagine how any such electron could be described as at rest.


Analogies and imagination are, alas, worthless. You have to start with the world as it is, then build a mathematical model that describes and predicts what you see. Whilst the Bohr atom is historically interesting, and the electron shell model is useful for inorganic chemistry (at least in gases and liquids), only a quantum orbital probability model describes and predicts all the observed properties of atoms and molecules.   
Title: Re: Are electrons affected by gravity?
Post by: MolonLabe on 11/10/2015 12:16:45
I know that the analogy of planets orbiting a sun is far too primitive, but I find it hard to imagine how any such electron could be described as at rest.


Analogies and imagination are, alas, worthless. You have to start with the world as it is, then build a mathematical model that describes and predicts what you see. Whilst the Bohr atom is historically interesting, and the electron shell model is useful for inorganic chemistry (at least in gases and liquids), only a quantum orbital probability model describes and predicts all the observed properties of atoms and molecules.   

I'm not sure how to respond to that, given that only yesterday I had to defend the concept of using maths to explain something. I was asking for an explanation as to how an electron could be stationary, given, as you say, that only a quantum orbital probability model is satisfactory.

Title: Re: Are electrons affected by gravity?
Post by: alancalverd on 11/10/2015 14:17:09
The quantum orbital probability model describes the distribution of electrons in atoms and molecules. Free electrons in vacuo behave as individual particles with charge -1 and mass 0.008 that can be made to move at pretty much any speed you want, including backwards, so there's no problem creating a stationary electron. Would such a thing be useful, I wonder? I think not, though Millikan's oil drop experiment measured the charge on a stationary body carrying one surplus electron. 

There's no problem describing your motion if you are standing still in the middle of a field, but the equation would look quite different if you were caught up in a tornado or a moving crowd.   
Title: Re: Are electrons affected by gravity?
Post by: MolonLabe on 11/10/2015 14:47:35
Because of this wavelike nature the electron can never be at rest on the ground. Unless it happens to be part of a static electric charge. However an electron as part of a molecule which makes up a solid CAN rest on the ground.

The quantum orbital probability model describes the distribution of electrons in atoms and molecules. Free electrons in vacuo behave as individual particles with charge -1 and mass 0.008 that can be made to move at pretty much any speed you want, including backwards, so there's no problem creating a stationary electron.

This is what I was querying, because your response looks to me like a direct contradiction to the other post I quote here.
Title: Re: Are electrons affected by gravity?
Post by: alancalverd on 11/10/2015 16:01:24
Read the first post carefully. It's clumsily expressed but basically tautologous: an electron cannot be at rest unless it is static.... I'd agree with that.
Title: Re: Are electrons affected by gravity?
Post by: jeffreyH on 11/10/2015 16:58:54
I would go with Alan's view if I were you. He is a professional.
Title: Re: Are electrons affected by gravity?
Post by: MolonLabe on 11/10/2015 19:47:36
The quantum orbital probability model describes the distribution of electrons in atoms and molecules.
Read the first post carefully. It's clumsily expressed but basically tautologous: an electron cannot be at rest unless it is static.... I'd agree with that.
I would go with Alan's view if I were you. He is a professional.

Perhaps I'm missing something here, but I can't go with anybody's view until they express it. Surprisingly, I had read the post very carefully. It included "However an electron as part of a molecule which makes up a solid CAN rest on the ground." This did not seem compatible with the statement "The quantum orbital probability model describes the distribution of electrons in atoms and molecules." I was hoping for some clarity.
Title: Re: Are electrons affected by gravity?
Post by: jeffreyH on 11/10/2015 19:55:59
The whole molecular system as a unit can rest on the ground as a solid. In which case the electron cannot be considered on its own. It also depends upon what you mean by 'rests'. That is more a macroscopic representation which will not apply in the microscopic domain.
Title: Re: Are electrons affected by gravity?
Post by: MolonLabe on 11/10/2015 20:04:30
The whole molecular system as a unit can rest on the ground as a solid. In which case the electron cannot be considered on its own. It also depends upon what you mean by 'rests'. That is more a macroscopic representation which will not apply in the microscopic domain.

Ah - ok. That clear's up my bafflement. Thanks.
Title: Re: Are electrons affected by gravity?
Post by: Jarek Duda on 22/08/2019 08:46:23
As gravity is like 39 orders of magnitude weaker than EM, it is extremely difficult to measure it for (charged) electron.

However, there is this 1967 Witteborn, Fairbank classical experiment with thermal electron source at the bottom and detector at the top: http://xdel.ru/downloads/lgbooks/fairbank_falling_electrons.pdf
(https://i.imgur.com/GOBLrPU.png)
Affected by gravity electrons should travel on parabola trajectories - what leads to maximal possible time between emission of thermal electron and its detection.

However, the experiment has shown no maximal time - leading to conclusion of nearly no gravitational attraction: "force was shown to be less than 0.09mg".

However, explanation has appeared later: that gravity created charge gradient in metal pipe used to screen the system - what turns out to exactly cancel eventual gravitational attraction on electron, no matter how strong it is.

So from this experiment we don't know, and I wasn't able to find a later successful one.
Title: Re: Are electrons affected by gravity?
Post by: evan_au on 22/08/2019 11:06:12
Quote from: Jarek Duda
gravity created charge gradient in metal pipe used to screen the system
Doesn't that imply that electrons feel gravity - and fall "down" until the electrical potential of the electron's charge inside the metal just balances the gravitational potential of the electron's mass?

That implies that there should be a very slight excess of electrons at the bottom of the metal tube, and a very small deficit of electrons at the top of the metal tube?

Is there a way we can measure electrical charge locally, without running an "Earth" lead down through Earth's gravitational field?

Quote from: OP
Are electrons affected by gravity?
There is a project running at CERN to determine whether antimatter is affected by gravity.
- They are trying to measure the gravitational acceleration of antimatter.
- Initially, they tried using antiprotons falling under gravity, but they found that, even with a carefully shielded experimental chamber in a hard vacuum, the electrical forces were about as large as the gravitational forces
- An electron in the same experiment will have about 2000x less mass than an antiproton, and 2000x less gravitational attraction than an antiproton, but experience the same electrical interference as an antiproton. That makes the electrical forces about 2000 greater than the gravitational forces on an electron.
- Then there is the difficulty of detecting that a single electron has passed the "finish line"; any electrical circuitry trying to measure the position of the electron will distort the result. (at least an antiproton provides a very clear victory cry in the form of a pair of high-energy gamma rays)
- Those antimatter gravity experiments are now going to experiment with neutral anti-Hydrogen, so now the stray electrical fields shouldn't bother them so much...
https://en.wikipedia.org/wiki/Gravitational_interaction_of_antimatter
Title: Re: Are electrons affected by gravity?
Post by: Hayseed on 22/08/2019 11:33:12
A simple experiment should show you that electrons are not affected by gravity.  Only electrons are involved.

Measure the current velocity in a horizontal conductor.  Now measure the current velocity of a vertical conductor.

An isolated charge.....has no gravitational field or properties.  There is much more isolated charge(matter) in the universe, than in the stars.  Stars have been spewing out isolated charge, since the first one lit up.  We can find NO evidence.......of this charge.....re-combining.  We have never seen a star form, only a suspected formation.  If stars are born, we should have images, because of the number(and time) of stars, that we have looked at.

We should have seen the kids.  But we only see the old ones.
Title: Re: Are electrons affected by gravity?
Post by: Jarek Duda on 22/08/2019 11:54:49
I don't know the details, but here are good 2015 slides:
https://indico.cern.ch/event/361413/contributions/1776296/attachments/1137816/1628821/WAG2015.pdf

Indeed there are a few ongoing CERN projects to measure gravitational weight of antimatter, but it seems there is certainty that it will be the same.

Also it is worth to mention that there are more types of masses:
1) energy (released in annihilation) E = mc^2
2) inertial in F=ma
3) gravitational
4) de Broglie's clock E = hbar * omega, confirmed experimentally for electron: https://link.springer.com/article/10.1007%2Fs10701-008-9225-1
We can assume that all of them are equal, but it is far from being experimentally confirmed.
1) <-> 2) is in special relativity. For 3) it was probably confirmed only for baryons. We don't know much about 4).
Title: Re: Are electrons affected by gravity?
Post by: thebrain13 on 03/12/2019 06:24:27
I can't believe after almost 13 years, this post still has action and has 38,000 views. Awesome lol