Chris Carlin

37 Followers
13 Following
274 Posts

By day I'm a physicist at a national lab in the US.

I'm generally interested in systems of all types, from interacting particles through economies through systems of law.

At the moment I'm especially interested in studying and engaging with the evolving norms of this distributed system, Mastodon build around ActivityPub.

@FenTiger

It's probably more like waves, bulk material sloshing back and forth, than acoustic frequencies.

It happens here during the cooldown as the system stays right on the knife edge of liquification, until it's liquified all it's going to, and then everything stabilizes.

I imagine there's a little hydrogen rainstorm going on in the chamber, but we can't look in to check. We have only our graphs and imaginations to explain them :)

@FenTiger

When I zoom in I can see the temperature variation rhythm against the pressure rhythm, and both signals have interesting overtones.

Cold plate is cooled at a certain rhythm BUT "warm" gas is physically moving back and forth against it, so they interact in a complex way, that may have resonant oscillations between cold pulses.

The geometry of the feed pipe will also influence the motion of the gas, adding more complexity.

This is why I chose this field.
Such interesting mysteries!

@FenTiger

That's the sort of good question that we can only speculate about!

System is a chamber with a cold plate in the middle and a pipe to an external tank of gas. Gas liquifies and falls to the bottom of chamber, pulling more in. All passive; no pumps.

Pressure sensors are back by the tank, and I see this noise is ~0.02 psi in amplitude.

The plate is cooled by a pulse tube cryocooler so plate temperature has very slight rhythmic variation in temperature.

Tiny surges in liquification?

@teovaldes @serenissimaj

It's a tricky discussion because it gets into varying concepts of what doctoral research and its goals should be in the first place, and people will often have diametrically opposed answers to those questions.

A lot of it might come down to different fields using the same terminology despite having evolved it in opposite directions over generations.

Also, I'll have you know a certain dissertation is basically bible to our everyday work in my lab!

Spending Sunday liquifying hydrogen in a test of our equipment before the next #experiment.

I sure wish #Mastodon didn't have the character limit so I could explain more about this for anyone who'd be interested :)

Green lines are temperatures of cold surfaces. Blue line is pressure of hydrogen being fed to it. Notably, the blue line dives as the plate temperature hits the vapor-pressure curve and H2 begins liquifying.

Experimental techniques in low-temperature #physics!
#Thermodynamics!

@timbray

At the risk of being utterly unhelpful :) I remember seeing a post from someone a few days ago celebrating that their client added some really great threading features recently.

Also, are you sure you need it to be a Mastodon client? Would you be open to a different Fediverse platform that handles threading better?

@JeroenSH

The big difference is that Gmail and other centralized services rose out of an environment of scarce computing resources, where computer power was expensive and communications unreliable.

It made sense to centralize then.

Today's environment is so different, where we have resources to afford decentralized inefficiencies for the sake of their benefits.

#Mastodon and #ActivityPub don't face the same pressures as email then.

@nswigger @Prof_BearB

They would find plenty to take them as an alternative to the hardliners currently mucking up their plans.

Their end of the deal would be specified in the Rules of the House, and given what we see here, they wouldn't be able to further alter the rules even if they wanted to get out of it.

@noellemitchell

You can think of Misskey and Calckey as alternatives to Mastodon, not just different instances but entirely different programs that are all compatible with each other.

They can have very different features.

But also, yeah, even Mastodon instances are free to set longer character limits.

But it might help if you said why you were looking for a new instance, to help get suggestions.

@shoq

Well, there are two different issues there, the tags themselves and the user interface/user experience system that processes them.

I think this is firmly on the side of Mastodon's UI needing to improve and give users more power to control their experiences.

Like you said, following who's in the list is one example of how the interface can stand to improve.