Optical interferometry and atomic clocks

30:47there is a famous um optical interferometer in Chile called the very large telescope VLT compared to the VLA but and what they do in order to do the interference they don't do computational interference they literally have tunnels underneath the ground that are routing the light >> physically >> so that the light physically interferes >> right >> right because that's like okay you can't you can't record the data and do do it computationally hardware is king, right? And even when it comes to astronomy, hardware is king, right? >> As we've discussed multiple times on the show. >> And so VT does it that way. But if if I wanted to rig up a a optical array

31:27that's the size of the Earth, currently it's not possible because we just don't have the timing complexity. Now, there are optical clocks that are getting to that level of accuracy, but like now deploying it across all of these telescopes and it it's it's a challenge, right? because it's still a very new technology >> but this is just to be clear this is an engineering problem >> not necessarily a fundamental science or physics problem at this point like we would know we we have potential paths well identified >> yes the potential paths are well identified I think realizing those paths there still might be some physics issues okay you know like like creating an optical clock that um that that is

32:08stable enough like I don't know much about and I think we're going to do future episodes on optical clock right this is a Comment below if you want this one because I'm because we we people always talk about oh we have atomic clocks but what we're saying is we they're not enough atomic clocks. Yeah. There's not enough decimal places. >> Yeah. Yeah. And if there aren't enough decimal places it's like only in Boulder, Colorado, right? There's like there's like a few groups in Boulder, Colorado that have this thing working. >> We have it for the nukes [laughter] but not for science. Let's make let's make the clocks for nukes work for science. That's what we want. So, so and and I I do also want to shout out there's um there's a team at Mount Wilson that we covered that also had um uh an optical

32:50interpherometer and they're the guys that like found sunspots on other stars. We covered that episode, but they also do the hardware thing. They've got like a tunnel with a bunch of lasers and like they're they're interfering it optically. Yes. So, so doing this which is really computational challenge we haven't been able to figure out for atomic for um optical >> optical telescope >> which is which is and the the description is really important because basically the what we're saying is radio waves travel through space >> slower >> than light does which is what we say when we mean when we say optical and so we we we have a >> no I should be clear radio waves travel at the same speed as optical the cycle

33:31the cycle the cycle by which >> the the wave like goes up and down slower slower, >> right? The speed of light is the same there. People are going to come at us. >> No, no, no, no, no, [laughter] no. That that's a fair distinction and excuse my excuse my misnomer there. That's a fair distinction. And like as a crude analogy, it's like we're a police with a police radar traing people go by, but the the rate at which we can see the up and down go is is too slow for the for the Dodge Charger, whatever the the Dodge the Bugatti. >> Yeah. Right. Right. The Dodge Charger. It's going to be fine. >> Wait, no, wait, hold on. Some people are going to be mad cuz there's there's the Trackhawks. There's some label of them that are fast, but the point >> Yeah, you got to like rig it up. [laughter]

34:11>> Um, but but we we just are not able to move as quickly to have enough enough >> uh discrete granularity from a measurement and timing to be do anything valuable. Yes. And that's kind of the And once we could be able to do that, it's it's a very big deal. Um