Lightnews — Scholar-powered news

Alan Nathan @pobguy.bsky.social · 44m

Make that 1840-1920

Alan Nathan @pobguy.bsky.social · 50m

Just got the library copy of "Born Equal: Remaking America's Constitution, 1860-1920", by Akhil Amar, my favorite constitutional historian. This will be the 4th of his books that I have read.

Alan Nathan @pobguy.bsky.social · 50m

Just got the library copy of "Born Equal: Remaking America's Constitution, 1860-1920", by Akhil Amar, my favorite constitutional historian. This will be the 4th of his books that I have read.

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Alan Nathan @pobguy.bsky.social · 1d

We all learn about quantum tunneling in atomic systems in introductory courses in quantum mechanics. The current Nobel Prize was for the observation of such tunneling in much larger systems, as initially predicted by my UIUC colleague Nobel Laureate Tony Leggett.
www.nytimes.com/2025/10/07/s...

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Alan Nathan @pobguy.bsky.social · 3d

Very nice article from Rod Cross:
pubs.aip.org/aapt/pte/art...

A Baseball Bat and Ball Collision Experiment for Students

When a batter strikes a ball, the outgoing speed of the ball depends on the swing speed of the bat, the incoming speed of the ball, and the impact point on the

pubs.aip.org

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Alan Nathan @pobguy.bsky.social · 4d

Curveballs have a downward Magnus force, which is reduced with a tailwind, making it more sustainable to the deadly hanging curveball.

Tangotiger @tangotiger.com · 5d

Tagging @pobguy.bsky.social for interest...

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Reposted by Alan Nathan

Gummy Arts @gummyarts.bsky.social · 5d

“The Twilight Zone” premiered on this date in 1959.

Colored-pencil card drawing of Rod Serling

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Alan Nathan @pobguy.bsky.social · 7d

Surely you jest!

Cecilia M. Tan @whyilikebaseball.bsky.social · 7d

You know what I miss? The curse of the Bambino. In the days of the curse, no way would the Yankees load the bases in the bottom of the ninth against Boston and not walk it off.

Also you know the Yankees never win a World Series with a republican in the White House.

#superstitions

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Alan Nathan @pobguy.bsky.social · 10d

As is by custom on this anniversary, I read again John Updike's great essay, with the words "God's do not answer letters."

Mister Bultitude @bultitude.bsky.social · 10d

“Less Than 11,000 Hub Fans Bid Kid Adieu” just doesn’t have the same ring

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Alan Nathan @pobguy.bsky.social · 10d

10,454 to be exact

Chairman Meow @chairman-meow.bsky.social · 10d

Less than 11,000 were in attendance, confirming that Boston fans are just the worst.

Alan Nathan @pobguy.bsky.social · 10d

Today is the 65th anniversary of Ted's last swing (shown below), resulting in his 521st home run.

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Alan Nathan @pobguy.bsky.social · 13d

The thing I find most interesting about the video is how quickly the vibrations are damped, despite being "free" (i.e., no hands).

Brian Mills @bmmillsy.bsky.social · 13d

We need @pobguy.bsky.social on the case!

Razzball @razzball.bsky.social · 13d

the bat moved like a high school Peter Pan production's 1st rehearsal

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Reposted by Alan Nathan

Barton L Smith @themagnuspi.bsky.social · 20d

If you know any kids that are interested in sports-ball aerodynamics or want to learn more yourself, take a look at this excellent article: www.snexplores.org/article/pitc...

Thanks to @pobguy.bsky.social for introducing Wendy and I.

How to make a pitched ball curve to your will

A range of tricks pitchers use to get curve all come down to the thin layers of air next to the ball — and how a ball’s spin and seams affect them.

www.snexplores.org

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Alan Nathan @pobguy.bsky.social · 21d

And guess what...it's my birthday too!!

Alan Nathan @pobguy.bsky.social · 21d

Happy Birthday to the US Constitution!

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Alan Nathan @pobguy.bsky.social · 21d

Happy Birthday to the US Constitution!

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Alan Nathan @pobguy.bsky.social · 22d

Here is a clip from that episode, "Nothing in the Dark":

youtu.be/9tfyv4BZRug

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Alan Nathan @pobguy.bsky.social · 22d

As we remember the life of Robert Redford, here is his appearance on The Twilight Zone (S3,E16, January 1962), featuring truly excellent performances by both Redford and (especially) Gladys Cooper.

V Design Detroit @vdesigndetroit.bsky.social · 22d

RIP Mr. Redford
One of my favorite Twilight Zone episodes "Nothing in the Dark".

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Alan Nathan @pobguy.bsky.social · 22d

As we approach the 50th anniversary of the "thrilla in Manila", Vann Newkirk has written a superb article about Ali and Frazier, their relationship, and the fight. It is as good a piece of sports writing as I've seen in recent years. I highly recommend.
www.theatlantic.com/magazine/arc...

The Greatest Fight of All Time

Fifty years ago, Muhammad Ali met Joe Frazier in Manila.

www.theatlantic.com

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Alan Nathan @pobguy.bsky.social · 24d

He was an excellent governor who knew how to work across the aisle, mainly with Mike Madigan, to get things done.

Craig Wieczorkiewicz @mwltraveler.bsky.social · 24d

I grew up and lived in Illinois most of my life. Jim Edgar is probably the last well-liked governor of that state. People on both sides of the aisle respected him, didn't trash talk him after he was out of power, and - most importantly - he was never involved in a scandal that landed him in prison.

Chicago Tribune @chicagotribune.com · 24d

Jim Edgar, the two-term Republican governor who guided Illinois through much of the 1990s with a low-key yet intense persona and a meticulous focus on fiscal matters aimed at preparing the state for the 21st century, died Sunday.

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Alan Nathan @pobguy.bsky.social · 24d

Yes

Jason @jasoner.net · 24d

Ok, so if I substitute that sqrt expression for v, then substitute vx - vwindx, vy - vwindy, etc, that should work?

Alan Nathan @pobguy.bsky.social · 24d

Radians/sec

Jason @jasoner.net · 24d

Also is omega spin rate (rpm) or angular velocity (radians per second)? I sort of assume the latter, but I figure it could be either

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Alan Nathan @pobguy.bsky.social · 24d

Almost. Since v= sqrt( vx^2+vy^2+vz^2), that must also be modified. Using v-vwind is not correct.

Jason @jasoner.net · 24d

@pobguy.bsky.social When using your baseball equations of motion, to account for wind, can I simply substitute (v - v_wind) for v, v_z - v_(wind in z direction) for v_z, and so on?

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Alan Nathan @pobguy.bsky.social · 25d

Since I can't watch Red Sox v NYY on MLB.TV, I'm listening to the audio. Great to hear Joe Castiglione again.

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Alan Nathan @pobguy.bsky.social · 27d

Today I am thinking of my classmate and friend Bill Caswell, one of the many victims of 9/11

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Reposted by Alan Nathan

Weather Applied Metrics @weatherapplied.com · 28d

❔How do temperature, pressure, and humidity alter ball flight... and how much does it actually matter?

Find out more about how weather impacts sports in our latest blog: blog.weatherapplied.com/how-atmosphe...

#weatherapplied

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Reposted by Alan Nathan

Gabe Schumm, Ph.D. @stripester.bsky.social · Sep 6

Induced vertical break, spin efficiency, seam-shifted wake—what do these buzzwords mean for a pitch trajectory? Explore using my Statcast-based pitch visualizer (physics modeling based on work of @pobguy.bsky.social). Updated daily with new pitching data!

gabes135.github.io/pitch-graphic/

Pitch Visualizer

Computational Physics Ph.D.

gabes135.github.io

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