StarTalk Radio Episode Summary:
Title: The Philosophy of Physics with Elise Kroll
Host: Neil deGrasse Tyson
Guest: Elise Kroll, Professor of Philosophy
Release Date: June 24, 2025

Introduction to the Philosophy of Physics

In this engaging episode of StarTalk Radio, astrophysicist Neil deGrasse Tyson delves into the intricate relationship between philosophy and physics with esteemed philosopher Elise Kroll. The conversation is co-hosted by comedian Chuck Nice, adding a layer of humor to the deep scientific and philosophical discourse.

Neil deGrasse Tyson opens the discussion by highlighting a new and uncharted topic for the show: the philosophy of physics. He introduces Elise Kroll, a professor specializing in this field, who recently authored the book "The Einstein Paradox: The Debate on Non-Locality and Incompleteness in 1935".

[02:12] Elise Kroll: “The title actually comes from Schrödinger. He had a folder in his archive labeled the Einstein Paradox, which contained correspondence exploring deep philosophical questions about quantum mechanics.”

Historical Context: Newton vs. Einstein

Elise Kroll provides a historical backdrop, tracing the evolution of physics from Isaac Newton to Albert Einstein. She explains how, during Newton's time, philosophers often doubled as physicists, seamlessly blending deep philosophical inquiries with scientific explorations.

[05:05] Elise Kroll: “Newton's 'Principia' doesn't even have equations in the first part. It's all about natural philosophy, which was essentially physics at the time.”

The conversation then shifts to Einstein, who, unlike Newton, was trained strictly as a physicist. Elise contrasts this with the modern specialization that often isolates philosophy from the physical sciences.

[07:40] Neil deGrasse Tyson: “So when you reduce your number of fat cells in your body, giving it up to energy, then you're reducing. It's a mass you're cutting from yourself.”

The Evolution of Specialization in Sciences and Philosophy

Elise Kroll discusses how, over time, the field became increasingly specialized, leading to a division where philosophers of science often require training in both philosophy and physics to contribute meaningfully to the scientific discourse.

[12:42] Elise Kroll: “We were able to be like, and you go to a conference in astrophysics nowadays, how many talks do you even are interested in? Like hyper-specialized.”

Chuck Nice humorously adds to this point, questioning the practical intersection of philosophy and physics in today's highly specialized academic landscape.

[09:08] Chuck Nice: “Yeah, I publish a paper, 100 people in the world will understand it or no, how many people in the world will care about it?”

Quantum Physics and Its Philosophical Implications

A significant portion of the episode is dedicated to the philosophical dilemmas posed by quantum mechanics. Elise Kroll elaborates on the foundational questions that emerged during the inception of quantum theory, highlighting the debates between prominent physicists like Einstein, Schrödinger, Heisenberg, and Bohr.

[22:33] Chuck Nice: “So let me ask you this. Often philosophy is thought of as a belief system.”

Elise emphasizes that philosophy in physics isn't about belief systems but about critical inquiries into the nature of reality, knowledge, and the methodologies underpinning scientific discoveries.

[25:25] Elise Kroll: “We come out of Newton, we go through Einstein, and these are still, they still make sense. Even if they're weird. You can still see why they make sense mathematically.”

Challenges in Quantum Cosmology

The discussion delves into the complexities of integrating quantum mechanics with general relativity—a quest that remains unresolved in modern physics. Elise Kroll points out that many of the interpretational debates in quantum mechanics are still ongoing, with no definitive answers in sight.

[47:33] Chuck Nice: “Yeah. At least what's coming.”

Neil deGrasse Tyson reflects on the persistent mysteries in quantum physics, citing phenomena like quantum entanglement and the instantaneous correlations it implies, which defy classical understanding.

[50:04] Neil deGrasse Tyson: “But some of the questions, I understand you correctly, we went from a quantum state to a macroscopic classical state. And there had to be a transition somewhere in there that allows us to bring these sensibilities together in a coherent understanding.”

The Role of Philosophy in Modern Physics

A recurring theme is the indispensable role that philosophy plays in framing and questioning the assumptions underlying physical theories. Elise Kroll argues that without philosophical inquiry, scientists might overlook foundational questions that could steer theoretical advancements.

[26:18] Neil deGrasse Tyson: “Many do. But I can tell you this. To the extent that I can understand myself, I leave all philosophical preconceptions at the door.”

However, Elise counters by asserting that complete neutrality is impossible, as scientists inherently carry personal and philosophical lenses that influence their interpretations and discoveries.

[27:43] Elise Kroll: “You can't do that, though. I said to the extent that I am able, I'm self-aware that I could be constrained by a philosophical thought.”

The debate touches upon the balance between objective scientific inquiry and the subjective influences of personal belief systems.

Philosophical Perspectives on Scientific Methodologies

Elise Kroll discusses how different philosophical viewpoints can lead to varying interpretations of the same scientific data. She uses the example of Kepler's attempts to align planetary orbits with Platonic solids, illustrating how philosophical inclinations can shape scientific hypotheses.

[24:40] Neil deGrasse Tyson: “It's simple and brilliant.”

Moreover, the conversation highlights how philosophical methodologies can either hinder or facilitate scientific progress, depending on how they interact with empirical evidence.

Conclusion: Science as an Endless Frontier

As the episode draws to a close, Neil deGrasse Tyson reflects on the nature of scientific exploration, emphasizing that as our knowledge expands, so does our understanding of what remains unknown. This perspective aligns with the idea of science being an "endless frontier," where each discovery opens new avenues for inquiry.

[53:10] Elise Kroll: “Seek and you will find. What's maybe not the case?”

[53:16] Neil deGrasse Tyson: “Seek and you may find the answer to the question you have not yet posed.”

Neil concludes by appreciating the profound yet often perplexing questions that arise at the intersection of philosophy and physics, underscoring the importance of maintaining a cosmic perspective in scientific endeavors.

Notable Quotes

• Elise Kroll on the accessibility of primary scientific literature:

  [03:15] Elise Kroll: “So why can't regular people read this? They sure can. It's just that the primary literature in particular, just reading the way that Einstein and Schrödinger and Heisenberg and Bohr talked to one another.”

• Neil deGrasse Tyson on the separation of philosophy and physics:

  [07:14] Neil deGrasse Tyson: “I'm distinguishing between people who go to school to be a philosopher and then attempt to contribute to the physical sciences, whereas that... you could do that in the day...”

• Elise Kroll on the impact of educational specialization:

  [13:01] Elise Kroll: “So this ties into your early question. It's like something about the extreme specialization has meant that in particular, the way we train physicists in the US even in high school is so divorced from the deep questions about but why, but how.”

• Neil deGrasse Tyson on the balance between knowledge and ignorance:

  [53:17] Neil deGrasse Tyson: “Seek and you may find the answer to the question you have not yet posed.”

• Elise Kroll on the intertwining of philosophy and scientific inquiry:

  [28:00] Elise Kroll: “The point is that you cannot. That you are going to walk in with some interpretive framework. Cannot be eliminated.”

Closing Thoughts

This episode of StarTalk Radio offers a compelling exploration of how philosophy underpins and propels the advancements in physics. Through the insightful dialogue between Neil, Chuck, and Elise, listeners gain a deeper appreciation for the nuanced interplay between abstract philosophical questions and tangible scientific discoveries. The discussion not only highlights historical shifts but also underscores the ongoing relevance of philosophical inquiry in tackling the mysteries that continue to challenge the boundaries of our understanding of the universe.