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Is Mathematics Mostly Chaos or Mostly Order?

Last winter, at a meeting in the Finnish wilderness high above the Arctic Circle, a group of mathematicians gathered to contemplate the fate of a mathematical universe.

It was minus 20 degrees Celsius, and while some went cross-country skiing, Juan Aguilera, a set theorist at the Vienna University of Technology, preferred to linger in the cafeteria, tearing pieces of pulla pastry and debating the nature of two new notions of infinity. The consequences, Aguilera believed, were grand. “We just don’t know what they are yet,” he said.

Infinity, counterintuitively, comes in many shapes and sizes. This has been known since the 1870s, when the German mathematician Georg Cantor proved that the set of real numbers (all the numbers on the number line) is larger than the set of whole numbers, even though both sets are infinite. (The short version: No matter how you try to match real numbers to whole numbers, you’ll always end up with more real numbers.) The two sets, Cantor argued, represented entirely different flavors of infinity and therefore had profoundly different properties.

Post-Alcubierre Warp-Drives

Researchers are actively exploring and revising the concept of Alcubierre warp drive, as well as alternative approaches, to potentially make superluminal travel feasible with reduced energy requirements and advanced technologies ## ## Questions to inspire discussion.

Practical Warp Drive Concepts.

🚀 Q: What is the Alcubierre warp drive? A: The Alcubierre warp drive (1994) is a superluminal travel concept within general relativity, using a warp bubble that contracts space in front and expands behind the spacecraft.

🌌 Q: How does Jose Natario’s warp drive differ from Alcubierre’s? A: Natario’s warp drive (2001) describes the warp bubble as a soliton and vector field, making it harder to visualize but potentially more mathematically robust.

🔬 Q: What is unique about Chris Van Den Broeck’s warp drive? A: Van Den Broeck’s warp drive (1999) uses a nested warp field, creating a larger interior than exterior, similar to a TARDIS, while remaining a physical solution within general relativity. Energy Requirements and Solutions.

💡 Q: How do Eric Lent’s hyperfast positive energy warp drives work? A: Lent’s warp drives (2020) are solitons capable of superluminal travel using purely positive energy densities, reopening discussions on conventional physics-based superluminal mechanisms.

Tesla Robotaxi Vs. Waymo

Tesla is planning to launch a robo-taxi service in Austin, Texas, which is expected to disrupt the market with its competitive advantages in data collection, cost, and production, shifting the company’s business model towards recurring software revenue ## ## Questions to inspire discussion.

Tesla’s Robotaxi Launch.

🚗 Q: When is Tesla launching its robotaxi service? A: Tesla’s robotaxi launch is scheduled for June 22nd, marking a transformational shift from hardware sales to recurring software revenue with higher margins.

🌆 Q: How will Tesla’s robotaxi service initially roll out? A: The service will start with a small fleet of 10–20 vehicles, scaling up to multiple cities by year-end and millions of cars by next year’s end, with an invite-only system initially. Tesla vs. Waymo.

📊 Q: How does Tesla’s data collection compare to Waymo’s? A: Tesla collects 10 million miles of full self-driving data daily, compared to Waymo’s 250,000 miles, giving Tesla a significant data advantage for training AI and encountering corner cases.

🏭 Q: What production advantage does Tesla have over Waymo? A: Tesla can produce 5,000 vehicles per day, while Waymo has 1,500 vehicles with plans to add 200,000 over the next year, giving Tesla a substantial cost and scale advantage.

Alzheimer’s: Bacteria that cause stomach ulcers may also protect brain

Every three seconds, someone in the world develops dementia. Alzheimer’s disease is the most common form of dementia, accounting for between 60% and 70% of all cases.

Although scientists have made significant progress in understanding the disease, there’s still no cure. That’s partly because Alzheimer’s disease has multiple causes—many of which are still not fully understood.

Two proteins which are widely believed to play central roles in Alzheimer’s disease are amyloid-beta and tau. Amyloid-beta forms sticky plaques on the outside of brain cells. This disrupts communication between neurons. Tau accumulates inside brain cells, where it twists into tangles. This ultimately leads to cell death. These plaques and tangles are the hallmark features of Alzheimer’s disease.

Japanese Journal of Mathematics

Information geometry has emerged from the study of the invariant structure in families of probability distributions. This invariance uniquely determines a second-order symmetric tensor g and third-order symmetric tensor T in a manifold of probability distributions. A pair of these tensors (g, T) defines a Riemannian metric and a pair of affine connections which together preserve the metric. Information geometry involves studying a Riemannian manifold having a pair of dual affine connections. Such a structure also arises from an asymmetric divergence function and affine differential geometry. A dually flat Riemannian manifold is particularly useful for various applications, because a generalized Pythagorean theorem and projection theorem hold. The Wasserstein distance gives another important geometry on probability distributions, which is non-invariant but responsible for the metric properties of a sample space. I attempt to construct information geometry of the entropy-regularized Wasserstein distance.