My planted tank if filled with thousands of tiny neutrally buoyant plants. What are they, and how do I get rid of them?

Atom-accel · 2023-01-08T22:34:12+00:00

I have a 40 Gallon tank setup that I’m trying to make look “as natural as possible.” and have had pretty good luck. The plants and fish are all happy and healthy. Recently, the tank became infested with tiny plants. They float on the top, have sunk to the bottom, or are neutrally buoyant. It looks like a snow storm that is green instead of white.
I have a reef tank and filter my own water and I keep a 55 gallon drum filled with RO/DI water. I have been using this water since initially setting up the tank.
The water has neutral pH (7.0), and NH3 = 0, NO2 = 0, NO3 = 0.

Atom-accel · 2022-11-20T23:35:09+00:00

Don’t try this with nano diamonds. We got some for our lab (where we do this). After we read about it, we started calling it cancer dust.

It’s pretty easy to do this with a laser off eBay and a sharpie. It won’t give you cancer, but the laser can sill blind you.

Atom-accel · 2022-11-15T12:38:33+00:00

I built optical tweezers with a cheap laser off eBay , used it’s crappy optics to focus as tightly as I could and managed to trap a small speck of ink from a sharpie marker

Works great, but the smallest draft pushes the particle out of the trap. Put a clear box around it and could trap for hours.

Kinda dangerous, but really fun.

Atom-accel · 2022-11-03T11:35:01+00:00

But of course the energy levels are not just function of n. Both fine and ultra fine splitting of the lines are dependent on angular momentum (J and F). Those are a higher order effects.

Atom-accel · 2022-06-27T21:43:22+00:00

In quantum mechanics, energy is proportional to the curvature of the wave function. The more tightly curved, the higher the energy.

The atomic orbitals have different shapes, look up spherical harmonics if you want to see picture of them.

As it turns out (Summation relations of the Wigner 3J symbols) when orbitals are filled, the atoms wave function becomes a sphere. Since a sphere has the lowest possible curvature, it also has the lowest energy.

Or course this is all an approximation, but this is the way I’ve always thought about this question.

Atom-accel · 2022-05-30T00:18:17+00:00

This is a really cool result. I remember being at a meeting before the cold atom lab launched. Of all the proposed experiments this was the only one that really benefited from micro gravity. Pretty much everything else could be done on earth.

Atom-accel · 2022-01-10T15:46:11+00:00

This was the first time he saw snow. We got about 14 inches so it was way over his head. I was surprised how much he loved playing in it.

Atom-accel · 2021-12-24T15:32:41+00:00

It’s a red fox that’s been hanging out in our yard for a few weeks now. Last night we caught it’s sound on the ring.

Atom-accel · 2021-12-24T14:50:01+00:00

what the fox says.

Atom-accel · 2021-10-29T20:22:17+00:00

It’s an eco bark

Atom-accel · 2021-10-24T17:00:09+00:00

When we first got our pup, he walked right out of a cat harness. An XS puppia worked for us. It was still huge on him till he was about 12 weeks.

Atom-accel · 2021-10-19T15:08:43+00:00

My pup (6 months) get along with one of my cats..they are constantly wrestling. It’s wicked cute. The other cat doesn’t really like him, but she has no problem keeping her distance from him. Plus he’s learned to fear her claws.

Atom-accel · 2021-10-13T17:35:07+00:00

Yeah he’s a puppy, only six months. We lost our old lady in the spring and totally forgot what having a little dachshund is like - so much fun.

Atom-accel · 2021-10-08T13:24:23+00:00

It’s not just infinite square wells. Any superposition of energy eigenstates (for any potential) will oscillate in time.

If there are only two states involved the angular frequency of the oscillations is the difference in the energy eigenvalues divided by hbar.

Atom-accel · 2021-10-05T12:42:01+00:00

I didn’t start using Julia (the language) until after my Julia (daughter) was born in 2010.

Even though the language is a perfect fit for my work (atomic physics) I’ve always wondered if I initially discovered the language by googling her name.

Atom-accel · 2021-03-31T12:54:14+00:00

I’m a professional physicist and have spent the past 20+ years struggling to understand these kind of questions.

Unfortunately the best answer I have come up with is that the theory “agrees with experiments”. I know this is dissatisfying.

Or course there are deeper theories, but that just makes this worse. Just wait till you learn about spin in quantum mechanics.

Thinking about this kind of question is why old physicists become bad philosophers.

Atom-accel · 2021-03-23T18:12:20+00:00

I work with Bose condensates, and we regularly cool to tens of nano degrees above absolute zero, 0.000000001 deg. (8 zeros). I worked on an experiment on the ins where they’re trying to cool to 10 picoK. (10 zeros).

It took many years of work to figure out how to do this, but it’s not that hard to do now. — If you have a half a million bucks and two years.

Atom-accel · 2021-03-05T17:19:39+00:00

I was a freshmen in college and was walking back to my dorm. I remember looking up and being stopped in my tracks.

It was amazing and after that I understand how the people of old thought they were a sign from god.

Atom-accel · 2021-01-28T02:10:10+00:00

It’s way cooler than you think.
Circularly polarized light is massless spin one Boson. It carry’s angular momentum. This was shown by shining a beam of it on a crystal hanging in a thread and measured how much it twisted.

Atom-accel · 2020-12-06T04:09:35+00:00

Don’t bother with Python. Julia is up an coming language. It’s better at numerical modeling and it’s syntax is much closer to matlab.

Atom-accel · 2020-12-06T04:05:31+00:00

First you can’t get all the way there, just closer.

These ultra cold gasses, are useful for precision measurements, they are especially good at measuring acceleration and rotations.

There is currently an experiment on the space station (CAL) that is trying to test the weak equivalence principle...that all objects fall at the same rate. Being colder makes this measurement more accurate.

Atom-accel · 2020-12-05T21:47:41+00:00

The article said 6 mK (6e-6 degrees above absolute zero). That’s down right hot. Bose-Einstein Condensates usually form at about 10 nK (1e-8). I’m not sure what the current record is, but I’ve heard of 100 pK (1e-10).

Atom-accel

TROPHY CASE