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Join us for our next meeting, featuring physicist John Ashmead, on Friday September 18 at 8 pm! This is an in-person meeting at St. Mary’s at Penn, 3916 Locust Street, in the Parish building behind the Sanctuary. All our meetings are free and open to the public.

John Ashmead has a BA in physics from Harvard, summa cum laude, and a masters in physics from Princeton. For several years he was an assistant editor for Asimov’s SF Magazine.
He is a frequent speaker at Philcon, Balticon, Capclave (& WorldCon & NASA) on Time Travel, Invisibility, Star Gates, Parallel Universes, and related topics. Recently he co-edited (with Darrell Schweitzer) Tales from the Miskatonic University: What evils lurk in the dark reaches of the Dewey Decimal System?
He has been working on a series of papers on the relationship between time and quantum mechanics: the basic question is “does quantum mechanics apply in the time direction” or if you prefer, “is time fuzzy?” This is one of the trickier frontiers in physics: time all smooth and unavoidable, quantum mechanics fuzzy and never quite as observable as one might hope. It’s a bit like wresting with a smoke demon. So he has been forced to ask: “how do we know what’s true?” “what makes a theory believable?” And the most important: “how do you prove a theory is false?” and “why do you want to?”
He will be speaking about “How to think about weird things?”
Between General Relativity (stretchy time, black holes, warp drives) and Quantum Mechanics (tunneling thru barriers, going through two doors at once, and—what is it about those dead-and-alive Schrödinger Cats?) science has certainly produced its share of weird things. How do we tell scientifically sound weird stuff from the latest outpourings of the flake factories? Falsifiability—give me something I can prove wrong!—is part of the answer. But not, as we will see, all of it. We discuss how to separate the physics from the phake; talk about the difference between “Quantum Woo” and “Quantum Wright” and put some hard numbers on those hard-to-pin down Schrödinger cats!
Recent guests at our monthly meetings have included Fran Wilde, Carmen Maria Machado, A. C. Wise, Josiah Bancroft, Tom Purdom, Jon McGoran, Madeleine Miller, Fonda Lee, Caitlin Rozakis, Jeanne Cavelos, Jonathan Lethem, Vandana Singh, PJ Manney, Jason Sanford, John Wiswell, A. T. Greenblatt, Cat Rambo, Jo Walton, Stephanie Feldman, Ray Nayler, Premee Mohamed, Randee Dawn, Ellen Datlow, Walter Hunt, and Gregory Frost.
Our meetings now alternate between remote (via Zoom) and in-person. Locations for in-person meetings are either at St. Mary’s Church at Penn, 3916 Locust Walk, Philadelphia PA 19104, or the Rotunda, 4014 Walnut Street, Philadelphia PA 19104.
All in-person meetings for 2026 will be at St. Mary’s at Penn, 3916 Locust Walk, in the Parish Building behind the Sanctuary.
Upcoming meeting schedule:

