<html><head></head><body><div><span data-mailaddress="firstname.lastname@example.org" data-contactname="Stuart LaForge" class="clickable"><span title="email@example.com">Stuart LaForge</span><span class="detail"> <firstname.lastname@example.org></span></span> , 7/3/2015 12:03 AM:<br><blockquote class="mori" style="margin:0 0 0 .8ex;border-left:2px blue solid;padding-left:1ex;"><br>I didn't mean that life couldn't exist *anywhere* in the modern
<br>universe, just that now it can only exist in relatively scarce oases
<br>like the earth. My point was once upon a time life could have existed
<br>everywhere even in the interstellar medium. I believe that it was once
<br>the rule rather than the exception but then most of it died.
</blockquote></div><div><br></div><div>There is a conflation here of right temperature range and being able to sustain life. Life requires a lot more than the right temperature, in particular elements that can form chemistry, lack of ionizing radiation that disrupts chemistry, and useful energy gradients to exploit. The early universe might have been room temperature, but the average density during this era was just a factor of 100 higher than now (3*10^-26 kg/m^3, a very high lab vacuum), the constituents were nearly all hydrogen and helium, and the radiation flux rather intense. </div><div><br></div><div>When people say "unlikely" about this scenario, they are not saying "one chance in a hundred", but "would require us to be totally wrong about everything we thought we knew about biochemistry and abiogenesis". </div><div><br></div><div><br></div><br><br>Anders Sandberg, Future of Humanity Institute Philosophy Faculty of Oxford University</body></html>