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<div class="moz-cite-prefix">On 2016-01-09 02:10, Will Steinberg
wrote:<br>
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cite="mid:CAKrqSyEsBfcmZ-dKuuTRavqGWcCkE2cZ9N8AO3iFERK=HdVUbQ@mail.gmail.com"
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<p dir="ltr">Can it be arbitrarily scaled up, though? Because
even if it would be practically impossible, that would still be
an interesting result. And maybe something to hold on to for
when we figure out fusion or make Dyson spheres. If it can't
scale though then it does kinda suck. </p>
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<br>
Gravity fields tend to suck :-) <br>
<br>
But, yes, the effect is small:<br>
<blockquote type="cite">The precision achieved by optical lattice
clocks in the measurement of a transition<br>
frequency is of the order 10^-15 [12]. Achieving such a
gravitational redshift with single-layered solenoids would require
CI = 10^-15, i.e. for an electric current of<br>
1kA, n = 100 it would require a solenoid length of about 10^11 m.</blockquote>
Now, CI scales with the square of the current and widning length.
The length is already on Dyson lengthscales, but you could of course
amp up the current by a mere factor of a few million to get order of
unity gravity effects. GigaAmpere currents doesn't sound that
impossible if you are using enormous superconductors. <br>
<br>
In the end this is likely the wrong way of making gravity. You could
use the energy to spin stuff up or move masses around. Electrical
fields get their energy divided by a c^2 factor when calculating
their gravity effect, so mass is way more effective in making
gravity.<br>
<br>
<pre class="moz-signature" cols="72">--
Dr Anders Sandberg
Future of Humanity Institute
Oxford Martin School
Oxford University
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