<story><title>Lasers could cut lifespan of nuclear waste from a million years to 30 minutes</title><url>https://bigthink.com/the-present/laser-nuclear-waste/</url></story><parent_chain></parent_chain><comment><author>yummypaint</author><text>I&amp;#x27;m a practicing nuclear physicist and do work on gamma ray interactions with actinides. It&amp;#x27;s possible i&amp;#x27;m missing something important, but i think this article is an utter mess and was clearly written by someone with absolutely no understanding of what they are saying. Attempting to learn anything from this article will be counterproductive.&lt;p&gt;Here is an explanation of chirped pulse amplification: &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.rp-photonics.com&amp;#x2F;chirped_pulse_amplification.html&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.rp-photonics.com&amp;#x2F;chirped_pulse_amplification.htm...&lt;/a&gt; 
This technique is for producing optical photons, which will have less than 10 ev of energy. In the same way that you can&amp;#x27;t focus the sun&amp;#x27;s light to a point that gets hotter than the surface of the sun (violates second law of thermodynamics), it isn&amp;#x27;t obvious how low energy laser pulses can be useful for this. The article offers no explanation whatsoever. Maybe the electric field across the nucleus can be made strong enough to induce scission?&lt;p&gt;In general, if you want to interact with the nucleus you need photons on the order of 1 Mev or more, whose wavelengths are comparable to the size of the nucleus. These are gamma rays, which are not optical photons. There are ways to boost optical photons to those energies (like inverse compton scattering), but the article says nothing about that either. I would think inverse compton scattering of a chirped pulse from an electron packet in an accelerator will completely destroy the sharp timing and reflect the distribution of the electrons instead.</text></comment>
<story><title>Lasers could cut lifespan of nuclear waste from a million years to 30 minutes</title><url>https://bigthink.com/the-present/laser-nuclear-waste/</url></story><parent_chain></parent_chain><comment><author>Jabbles</author><text>&lt;i&gt;uranium 235 and plutonium 239, have a half life of 24,000 years&lt;/i&gt;&lt;p&gt;- U235 has a half life of 700,000,000 years.&lt;p&gt;&lt;i&gt;If he gets pulses 10,000 times faster, he says he can modify waste on an atomic level.&lt;/i&gt;&lt;p&gt;The article says nothing about how he hopes to gain 4 orders of magnitude. Is there some kind of Moore&amp;#x27;s law in the &amp;quot;speed&amp;quot; of these pulses?&lt;p&gt;I wasted my time reading this article, it explains nothing.</text></comment>