<div dir="ltr"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><br></div><div class="gmail_extra"><div class="gmail_quote">On Fri, May 27, 2016 at 1:04 AM, spike <span dir="ltr"><<a href="mailto:spike66@att.net" target="_blank">spike66@att.net</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"></blockquote>
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<div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">> </div>Unless I misunderstood, LIGO has run a total of 18 days so far, and never with full instrumentation</blockquote><div><br></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"></div><font size="4">And about the time the 2 LIGO detectors come back online and at increased power (around September) it should be<div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"> </div>joined by a third detector, Virgo in Italy. Gravity waves are sort of opposite to light, with light it's easy to tell the direction the photon came from but hard to tell how far it has traveled, but with gravity waves it's easy to tell how far they have come but hard to tell from what direction; but with 3 detectors we can use triangulation to figure out where to point our optical telescopes<div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">,</div> and <div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">that </div>could help us figure out if the Black Holes came from dead stars or were primordial. I<div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">f</div> they come from dead stars then there may gas and dust nearby that will get heated to incandescence <div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">by the gravity waves </div>that our optical telescopes can see, but if they're<div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"> </div>primordial then there is a better chance<div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"> </div>they're in the cosmic boondocks between galaxies with no gas or dust nearby <div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">to heat up </div>and our<div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"></div> telescopes<div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"> will see no optical counterpart. </div></font><br></div><div><span style="font-family:arial,helvetica,sans-serif"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"><br></div></span></div><font size="4">A cool thing is if it can find them at all it should be able to hear gravitational waves over a vast distance because LIGO doesn't detect the energy in the <div class="gmail_default" style="display:inline">gravitational<font face="arial, helvetica, sans-serif"></font></div> waves<div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">,</div> it detects how much they alter the distance between a LASER and a mirror<div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">,</div> and that alteration only decrease linearly with distance; telescopes work with light intensity and that decreases with the square of distance not linearly.</font><div><font face="arial, helvetica, sans-serif"><div class="gmail_default" style="display:inline"><br></div></font></div><font size="4">It doesn't seem possible to tell when the distance between a LASER and a mirror 4 kilometers away changes by one ten thousandths the diameter of the nucleus of a atom ( equivalent to telling when the distance between Earth and Alpha Centauri changes by the width of a human hair)<div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">,</div> but incredibly they can. But as you point out as good as experimenters have become they still aren't good enough to find ET. Or ESP.<div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"> Maybe because there is nothing to find.</div></font></div><div class="gmail_quote"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"><font size="4"><br></font></div></div><div class="gmail_quote"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"><font size="4"> John K Clark</font></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"><div class=""><div class="h5"><br><br>
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