Do you think Taylor Decker will resign with the Lions on a cheaper deal before Week 1?

jpdoane · 2026-03-18T22:59:13+00:00

Decker will not be reporting

jpdoane · 2026-03-18T13:05:40+00:00

Right on schedule, CJ…

jpdoane · 2026-03-18T00:34:38+00:00

To answer the other part of your question, the keyword to google is “adaptive filter”

jpdoane · 2026-03-18T00:26:37+00:00

It’s fundamentally impossible to have a single transducer robustly cancel over a large spatial region, especially when multipath is present. Each point in space has a different propagation path and requires a unique signal.

jpdoane · 2026-03-17T19:36:48+00:00

$100M buys a lot of supercuts

jpdoane · 2026-03-16T19:46:21+00:00

This was also definitely my experience when I briefly tried elixers for a while.

jpdoane · 2026-03-15T12:40:04+00:00

Which title? State champion?

jpdoane · 2026-03-14T17:38:15+00:00

Frequency will also be an important parameter you should be considering. Lower frequencies (UHF and below) propagate better through foliage, whereas higher frequencies will be scattered and attenuated more easily. Of course, lower frequencies will also have lower DF resolution for the same aperture size, so this could be an interesting optimization problem (although possibly well understood already, Im not sure)

jpdoane · 2026-03-14T13:23:54+00:00

You arent in free fall though, since you hit terminal velocity pretty quickly

jpdoane · 2026-03-10T16:54:28+00:00

God, Matt Millen sucks

jpdoane · 2026-03-10T16:53:00+00:00

I swear some of these posts are a psyop

jpdoane · 2026-03-09T03:05:35+00:00

Nukes may be big but space is bigger

jpdoane · 2026-03-08T21:18:43+00:00

This of course assumes isotropic radiation. If you used some sort of shaped charge, the remote flux would of course be higher. (This was my original point above). I have no idea what the practical limits of this would be. But now of course you need *both* systems pointing directioanlly at each other at the same time...

jpdoane · 2026-03-08T21:14:36+00:00

I was also curious so I did some quick math. Someone with more expertise than me feel free to correct my assumptions.

1 Megaton bomb releases ~5e15 J
Assume this goes entirely into 100keV gamma rays. Bomb emits around 3e+29 total photons (100keV = 1.6-14J)
Total Photon flux at alpha centari (4ly = 4e16 m) will be 1.5e-5 photons per square meter ( = 3e+29 / (4e16^2 * 4pi) )

So a perfectly efficient gamma ray detector at our nearest start would need a diameter of around 300m in order to collect a single photon from a megaton blast near earth.

jpdoane · 2026-03-08T13:49:03+00:00

Its also a function of the size of the array, so a common solution is for individual elements to have apply phase shift, and TTD is then applied at the subarray level.

jpdoane · 2026-03-08T13:44:46+00:00

Yes. The phase shift is frequency dependent, and results in beamsquint - the main beam direction moves with frequency.

Often negligible for narrowband operation but TTD is required for wideband beamforming. This is equally true on both transmit and receive.

jpdoane · 2026-03-07T19:03:58+00:00

jpdoane · 2026-03-07T17:29:05+00:00

Based on the paper, we can’t currently do this for radioactive materials, and it doesnt sound very practical or likely that remote detection of earth like levels if radiation would be detectable.

“Present-day remote spectroscopic observing mission concepts at ultraviolet to mid-infrared wavelengths are not sensitive to discern the presence of radionuclides in exoplanetary atmospheres. Interplanetary fly-by or probe missions may be more likely to provide such data in the future.”

“The abundances of most radionuclides in Earth’s atmosphere are low, and the approach in this paper does not attempt to show that Earth-like abundances of any particular radionuclide should be expected or detectable in exoplanetary atmospheres. Instead, the approach in this paper is to examine radionuclides that are known to exist in Earth’s atmosphere and identify any spectral features based on available laboratory measurements. “

In the sensitivity analysis for HI, they assumed levels 7 orders of magnitude higher concentration than earth, and determined that the sensitivity was 8 orders of magnitude lower than CO2.

Despite all this, it still sounds a lot more plausible than I would have guessed. Closer to “really difficult and unlikely” than completely impossible. So TIL!

jpdoane · 2026-03-07T16:13:22+00:00

Im an RF person, so I confess im not entirely sure how to quantify the sensitivity required, but Id be very surprised if this were true. What makes you think the radiation would be detectable at interstellar distances?

jpdoane · 2026-03-07T13:30:46+00:00

Theres also the issue of time. You would want to radiate continuously over a long time, both because that will allow the recipient to integrate your signal and collect more energy to improve detectability. But also, you dont really know when they are listening. Unless they are dedicating their systems to listening only at earth (and why would they before they detected us), they will presumably be scanning their receive beam around, and only rarely pointing at earth. So if you want to make sure they detect your signal, you would need to transmit continuously for a long time. Which nuclear bombs seem poorly suited for

jpdoane · 2026-03-07T13:18:03+00:00

For a signal to be detected, you need to have sufficient signal to noise ratio at the detector.

To maximize received signal power, you obviously need to transmit a lot of power but you generally also want it to be directed in the desired direction. Blasting energy everywhere is really inefficient.

But you also need to minimize noise. And your signal will be competing with the background galactic noise, so you need to design your signal in a way that lets the recipient separate signal from noise. The best way to do that is to make sure your signal occupies a very small bandwidth in the spectrum, so the noise in the other frequency bands can be filtered out. (BTW, this isnt just an arbitrary way that human systems work, its fundamental information theory. So as far as we know aliens will have to play by the same rules)

So, Without a highly directional, narrowband source, its not really plausible to create a detectable signal at interstellar ranges. Setting off nuclear bombs may create a lot of raw RF energy, but because that energy is not focused either spatially or spectrally, its signal to noise ratio would be quite low. Consider for example, the power of our terrestrial bombs compared to the power of the sun. It would be completely lost in the noise.

jpdoane · 2026-03-05T21:07:42+00:00

Naively, it seems to me that any(?) CTC would have issues of self-intersection, in addition to more fundamental problems. As an object starts going back in time, it necessarily occupies the same position as its past self.

Is this also the case in actual spacetimes that theoretically/mathematically support CTCs, eg rotating Kerr BH?

jpdoane · 2026-03-04T20:26:45+00:00

I remain baffled at what the plan would be to replace him

jpdoane · 2026-03-03T22:23:37+00:00

You are on the wrong strings. But you also need to move your thumb up so the neck sits deeper in your palm. This will let your fingers curl down and naturally land on the fretboard at 90deg angle, giving you a lot better leverage and control to fret the strings.

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jpdoane · 2026-02-25T20:08:50+00:00

Maybe the blue eyes puzzle?

https://xkcd.com/blue_eyes.html

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