Natural Sciences

Gravity follows Newton and Einstein’s rules, even at cosmic scales

By tracking galaxy clusters hundreds of millions of lightyears apart, Penn physicist Patricio Gallardo and collaborators find that the laws of gravity written by Newton and Einstein still hold, leaving little doubt that invisible dark matter exists

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graduate research student working in thermal architecture lab at pennovation center

Upcoming Events

A purple sign labelled "Baltimore Avenue" hanging from a lamppost. The flag includes townhouse/building designs. Special Events

2026 Baltimore Avenue Dollar Stroll

Local businesses and community vendors will participate in a semiannual West Philadelphia tradition by offering special one-night-only deals for $1, $3, or $5. Local musicians and artists will provide entertainment up and down Baltimore Avenue, from 40th Street to 51st Street.

A church bell at St. Mary’s Church. Special Events

Toll the Bell 2026

Toll the Bell is a citywide sound installation bringing greater awareness to the gun violence epidemic affecting our city and the nation. At 1 p.m. on June 5, National Gun Violence Awareness Day, a prolonged period of bell ringing and other sound-making will take place at 30-plus locations across the city and beyond.

Cynthia Otto with black lab balancing on a rubber ball Special Events

Lessons from Listening to Dogs & Other Amazing Animals

In honor of her retirement after more than 35 years of service to Penn Vet, Cynthia M. Otto, professor of working dog sciences & sports medicine and executive director of the Penn Vet Working Dog Center, will share lessons learned from her animal companions, including a cat, a vulture, a puffer fish, several working dogs. Free and open to the Penn community. Register to attend.

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Supporting our Community

Building Community, Combatting Antisemitism, Countering Hate, and Supporting Every Member of the Penn Community

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Title IX Compliance in Athletics

Penn's Title IX Resolution with the U.S. Department of Education Office for Civil Rights

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Penn Priorities

A look at a few of our big picture priorities that improve Penn as we create knowledge to benefit the world.

Equal Opportunity and Nondiscrimination at Penn

The University of Pennsylvania seeks talented students, faculty, and staff with a wide variety of backgrounds, experiences, and perspectives. The University of Pennsylvania does not discriminate on the basis of race, color, sex, sexual orientation, religion, creed, national origin (including shared ancestry or ethnic characteristics), citizenship status, age, disability, veteran status or any other class protected under applicable federal, state, or local law in the administration of its admissions, financial aid, educational or athletic programs, or other University-administered programs or in its employment practices. Questions or complaints regarding this policy should be directed to the executive director of the Office of Equal Opportunity Programs; Franklin Building, 3451 Walnut Street, Suite 421, Philadelphia, PA 19104-6106; or (215) 898-6993.

Nondiscrimination Statement