Carl Rodriguez
@carlrodriguez.bsky.social
Professor of astrophysics at UNC, studying colliding black holes, swarming stars, and other things that go bump in the night. Big fan of transit, biking, climbing, Durham NC, he/him
dynamics.unc.edu
dynamics.unc.edu
This is fully consistent with our predictions going back almost 10 years at this point (our Cluster Monte Carlo models even make an appearance in the paper)!
October 28, 2025 at 4:25 PM
This is fully consistent with our predictions going back almost 10 years at this point (our Cluster Monte Carlo models even make an appearance in the paper)!
Probably three: two black holes merged, then their daughter product found another black hole and merged again. From the paper:
October 28, 2025 at 4:13 PM
Probably three: two black holes merged, then their daughter product found another black hole and merged again. From the paper:
Also one of them (GW241110) is the first binary black hole where the spins of the merging black holes are *anti-aligned* with the orbital angular momentum. That's a specific prediction of binaries formed in dense star clusters like globular clusters.
October 28, 2025 at 3:29 PM
Also one of them (GW241110) is the first binary black hole where the spins of the merging black holes are *anti-aligned* with the orbital angular momentum. That's a specific prediction of binaries formed in dense star clusters like globular clusters.
In this paper, we're look only at two clusters from our earlier Great Balls of Fire series. These clusters are on wildly different orbits and produce wildly different streams. Because the galaxy it is very messy, it produces bizzare features in the streams (which you might mistake for dark matter)
September 5, 2025 at 4:59 PM
In this paper, we're look only at two clusters from our earlier Great Balls of Fire series. These clusters are on wildly different orbits and produce wildly different streams. Because the galaxy it is very messy, it produces bizzare features in the streams (which you might mistake for dark matter)
Great paper on stellar streams led by Carnegie Postdoc Nondh Panithanpaisal. Specifically, streams formed by globular clusters pulled apart by the gravity of their host galaxies. But because they trace the full gravitational potential, they're an excellent way to measure dark matter in galaxies.
September 5, 2025 at 4:59 PM
Great paper on stellar streams led by Carnegie Postdoc Nondh Panithanpaisal. Specifically, streams formed by globular clusters pulled apart by the gravity of their host galaxies. But because they trace the full gravitational potential, they're an excellent way to measure dark matter in galaxies.
I like this because it's what we expect from globular clusters, which have the right type of old stars (low metallicity) and can dynamically pair black holes in their dense cores. These clusters are found in just about every galaxy, and are almost as old as the Universe itself.
August 26, 2025 at 1:30 PM
I like this because it's what we expect from globular clusters, which have the right type of old stars (low metallicity) and can dynamically pair black holes in their dense cores. These clusters are found in just about every galaxy, and are almost as old as the Universe itself.
If your binary black hole comes from a stellar binary, you expect the BH spins to be pointed in the same direction (positive values of Xeff). From a cluster, you expect them to be random (equal number of positive and negative Xeff). (like in this great diagram from @astronerdika.bsky.social)
August 26, 2025 at 1:30 PM
If your binary black hole comes from a stellar binary, you expect the BH spins to be pointed in the same direction (positive values of Xeff). From a cluster, you expect them to be random (equal number of positive and negative Xeff). (like in this great diagram from @astronerdika.bsky.social)
Ok, there's a lot of cool stuff in the new @ligo.org collaboration paper (and I'll let the actual LVK members talk about most of it), but one very cool thing from the populations paper (arxiv.org/abs/2508.18083) that jumps out to me is this plot of the effective spin for 30-40 solar mass BHs: 🔭🧪
August 26, 2025 at 1:30 PM
Ok, there's a lot of cool stuff in the new @ligo.org collaboration paper (and I'll let the actual LVK members talk about most of it), but one very cool thing from the populations paper (arxiv.org/abs/2508.18083) that jumps out to me is this plot of the effective spin for 30-40 solar mass BHs: 🔭🧪
CAREER proposal asking the important questions
July 22, 2025 at 8:36 PM
CAREER proposal asking the important questions
Me writing about stellar streams and dark matter:
July 11, 2025 at 3:02 PM
Me writing about stellar streams and dark matter:
Also of note/horror: this budget makes the 30M downselect explicit (GMT, not TMT) --
May 30, 2025 at 9:29 PM
Also of note/horror: this budget makes the 30M downselect explicit (GMT, not TMT) --
Damn even the Babylon Bee is clowning on Trump at this point?
May 13, 2025 at 5:04 PM
Damn even the Babylon Bee is clowning on Trump at this point?
Since when does research.gov use three explanation points?
May 6, 2025 at 9:16 PM
Since when does research.gov use three explanation points?
This title/picture combo is the funniest Veep-esqe shit I’ve ever eeen
March 28, 2025 at 7:27 PM
This title/picture combo is the funniest Veep-esqe shit I’ve ever eeen
If I email you before 9AM it's being sent from on top of a dog
March 25, 2025 at 12:55 PM
If I email you before 9AM it's being sent from on top of a dog
lol I’ve started getting ads trying to convince me to move my research career to Denmark.
February 26, 2025 at 2:39 PM
lol I’ve started getting ads trying to convince me to move my research career to Denmark.
Perturbation theory was a mistake
January 22, 2025 at 2:29 PM
Perturbation theory was a mistake
Finals week = dog office hours
December 10, 2024 at 3:10 PM
Finals week = dog office hours
Ok thanksgiving wasn't *that* bad.
December 1, 2024 at 4:03 PM
Ok thanksgiving wasn't *that* bad.
Also lmao I'm only using this from now on
November 26, 2024 at 11:04 PM
Also lmao I'm only using this from now on
First race! Half marathon in just under 2 hours.
Some nasty hills on this one…
Some nasty hills on this one…
October 20, 2024 at 8:18 PM
First race! Half marathon in just under 2 hours.
Some nasty hills on this one…
Some nasty hills on this one…
This is the most Klingon-core thing I've ever heard
August 11, 2024 at 9:22 PM
This is the most Klingon-core thing I've ever heard
In Madison for (my first!) AAS meeting; who else is around?
June 11, 2024 at 4:51 PM
In Madison for (my first!) AAS meeting; who else is around?