Charge in free fall

[swansont]

5 minutes ago, John Ye said:

You mean that radiation is small (non zero) when accelerating and  large when decelerating. They are not equal in quantity? That might be true due to non ideal experiment environment. If absolutely ideal, the radiation should be zero at accelerating stage.

That's your assertion, which is unsupported by physics. The radiation should be related to the acceleration, which is much larger at the stopping part of the experiment, than the "getting electrons up to speed" part of the experiment.

Which is why I suggested the antenna as an example.

5 minutes ago, John Ye said:

We can make real experiments. Detect radiation in each stage, radiation in   accelerating stage will not be detectable.

Because it's a small amount and will be hard to detect. Take Phi's direction and go open a thread in speculations with the details of an an experiment that will show that the radiation is zero

[John Ye]

7 hours ago, swansont said:

Deceleration is lay terminology. Acceleration is acceleration. The direction is a mere detail. 

Radiation from antennas is continuous, meaning it radiates while the charges speed up, and while they slow down.

Which is obviously not true. See comment above.

And of course we also have cyclotron radiation, in which the radiation is perpendicular to the velocity.

Cyclotron's electrons are not driven by only one force. Two forces are involved: electric force, and magnetic force. So the are circular moving, and are radiating energy.

7 hours ago, swansont said:

Radiation from antennas is continuous, meaning it radiates while the charges speed up, and while they slow down.

In one wave period, stopping radiation will not make the wave stop. Just like that we use a half sine wave to stimulate water, as long as the half sine keep repeating, the water waves continue.

We keeps throwing rocks into water, if repeating frequently enough, we can get a continuous wave. 

Edited September 4, 2018 by John Ye

[John Ye]

7 hours ago, swansont said:

That's your assertion, which is unsupported by physics. The radiation should be related to the acceleration, which is much larger at the stopping part of the experiment, than the "getting electrons up to speed" part of the experiment.

Which is why I suggested the antenna as an example.

Because it's a small amount and will be hard to detect. Take Phi's direction and go open a thread in speculations with the details of an an experiment that will show that the radiation is zero

OK, thanks. I will stop here, and open another speculation thread then we discuss this there.

 

Edited September 5, 2018 by John Ye