StarTalk Live Podcast: Science Is Everywhere with Neil deGrasse Tyson & Brian Greene -StarTalk @ BAM

Neil deGrasse Tyson introduces the StarTalk Live event at BAM, explaining that it will feature three segments: StarTalk flagship, StarTalk All Stars, and StarTalk Playing with Science. He then brings out his comedic co-host Chuck Nice and introduces theoretical physicist Brian Greene, known for popularizing String Theory and the Multiverse.

Brian Greene discusses recent news about the earliest star formed in the universe, approximately 180 million years after the Big Bang. He explains that these stars are detected indirectly by their impact on the Cosmic Microwave Background Radiation. The discussion then shifts to the unexpected strength of the signal from these early stars, prompting scientists to 'tweak' existing theories, possibly involving dark matter. They also touch upon the evolving understanding of the universe's expansion rate and dark energy, and how new observations might require rethinking gravitational force.

The conversation explores ideas about what existed before the Big Bang. Brian Greene presents two main concepts: the Multiverse, where our Big Bang is just one of many, and the idea of a cyclic universe, where the Big Bang results from the collision of 'slices of space' (branes) in higher dimensions. This leads to a discussion of whether these concepts push the question of 'what was before' even further or suggest an eternal, cyclical existence.

Neuroscientist Heather Berlin joins the stage, along with Chuck Nice and Neil deGrasse Tyson, to discuss the intersection of neuroscience and physics concerning free will. Brian Greene argues that physics suggests free will is an illusion, as human actions are governed by physical laws. Heather Berlin supports this view from a neuroscientific perspective, citing experiments (like Benjamin Libet's and fMRI studies) that show brain activity precedes conscious intention. They propose that the sensation of free will is an evolutionary illusion, providing a sense of control crucial for survival and social behavior, contrasting with fatalism.

Heather Berlin continues the discussion by suggesting that time, as we experience it, is also an illusion manipulated by the brain. She describes experiments using transcranial magnetic stimulation to alter the perception of past intentions and future actions. Brian Greene argues that while our *experience* of time can be manipulated and is counterintuitive compared to physical time (relativistic effects), time itself is a real physical quantity. They discuss the concept of 'flow states' where the sense of self and time diminishes, and potential future technologies for manipulating time perception.

The final segment, 'Playing with Science,' welcomes Olympic Silver Medalist figure skater Sasha Cohen. She describes the intense physical and mental demands of figure skating, including the precise 'torque' needed for jumps and spins. Neil deGrasse Tyson breaks down the physics of angular momentum in spins, explaining how bringing limbs closer to the body increases rotational speed due to conservation of angular momentum. There's a playful discussion about how added weight might affect performance.

Heather Berlin explains why figure skaters don't get dizzy: it's not 'spotting' like ballerinas, but rather training the brain to habituate to the sustained rotation. She details the role of the inner ear's fluid-filled tubes and how the brain processes conflicting sensory information during and after spinning. The conversation also touches on how altered mental states, like those experienced during intense performance, or even simple childhood spinning, tap into unique brain states that can be pleasurable or disorienting.