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Silas
2002-Feb-25, 02:28 PM
I received a lovely bit of pseudo-science in the mail, with a request for feedback. Well, I fed back, all right... The thing was full of the usual nonsense... My favorite was that heat is energy (yes) and that atoms have a "heat field" that contains that heat energy (no!)

However, one of the things the bloke said made me wonder: in his fantasy physics, electrons do not have gravitational mass.

So here's my question: we have a very good measure of the inertial mass of the electron... But has the gravitational mass of the electron been measured? I couldn't find any references... In the world of the electron, gravity is a distant and trivially weak force, and there are so many other forces pulling and pushing on one... I'm not really even sure how one would measure an electron's rate of fall...

Silas

Wiley
2002-Feb-25, 03:18 PM
Hmmm...

Electrons don't have gravitational mass? I kinda like this theory. How can you disprove it? You can't directly weigh an electron. (I am now envisioning a middle school physics class with triple beam balances and really tiny tweasers.)

No difference between gravitational mass and inertial mass has been found, and the current experiments are accurate to thirteen significant figures. Since this principle is well established and direct measurement of an electron's gravitational mass would be difficult, I'll doubt you'll find any papers dealing directly with the subject. Perhaps, there are papers that deal with it indirectly, like in particle accelerators that would use this equivalence to account for the effect of gravity on the particle.

John Kierein
2002-Feb-25, 05:55 PM
I think that you can measure the charge to mass ratio of the electron using the cathode ray tube method. I think the mass is the gravitational mass in that case.

Wiley
2002-Feb-25, 06:25 PM
On 2002-02-25 12:55, John Kierein wrote:
I think that you can measure the charge to mass ratio of the electron using the cathode ray tube method. I think the mass is the gravitational mass in that case.

This would be inertial mass. The force is electrostatic, F = q E. The resulting acceleration and deflection would give inertial mass.

My thought is to modify this experiment to balance the electostatic force with gravity, m g - q E = 0 and no deflection. If it can be done, then the electron has a gravitional mass. Of course, you would need a really long CRT.

<font size=-1>[ This Message was edited by: Wiley on 2002-02-25 13:27 ]</font>

<font size=-1>[ This Message was edited by: Wiley on 2002-02-25 13:28 ]</font>

Silas
2002-Feb-25, 10:29 PM
On 2002-02-25 13:25, Wiley wrote:

On 2002-02-25 12:55, John Kierein wrote:
I think that you can measure the charge to mass ratio of the electron using the cathode ray tube method. I think the mass is the gravitational mass in that case.

This would be inertial mass. The force is electrostatic, F = q E. The resulting acceleration and deflection would give inertial mass.

My thought is to modify this experiment to balance the electostatic force with gravity, m g - q E = 0 and no deflection. If it can be done, then the electron has a gravitional mass. Of course, you would need a really long CRT.

I'm sitting here grinning like a fool, envisioning such a long CRT...

Seriously, though... The CERN and other groups do a lot of work accelerating electrons and positrons... Do they have to correct for gravity?

(At one point, weren't people seriously considering the possibility, however vastly remote, that antimatter was also antigravity? IIRC, they took a long time to create enough antiprotons to demonstrate that antimatter was attracted to ordinary masses.)

There is a difference between "pseudo-science" and a "dumb guess."

Silas

2002-Feb-26, 01:53 PM
<a name="20020226.7:19"> page 20020226.7:19 aka was 6:26
however the thought police captured that moment in time SO?
http://www.yahoo.com/
http://webcrawler.com/ http://www.infind.com/
http://www.multnomah.lib.or.us/lib/ref/search.html
try 2 find this yourself
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