Everything you ever wanted to know about parallel universes, time, entropy, free will and more, explained by physicist Sean Carroll.
Up next, Michio Kaku: The Universe in a nutshell (Full Presentation) ► https://youtu.be/0NbBjNiw4tk.
Do you have free will? Is our Universe the only one, or do we live in one of many? And what does Einstein’s theory of relativity really say about the nature of reality?
These are some of the big questions that theoretical physicist Sean Carroll tackles in this Big Think video.
In 2022, Carroll published The Biggest Ideas in the Universe: Space, Time, and Motion, a book that achieves that rare feat of detailing the inner workings of scientific concepts in a way that’s accessible but not overly simplistic.
THE MULTIVERSE
In light of Whitney Houston and Bobby Brown’s daughter, Bobbi Kristina being found unconscious, there have been many headlines that said she in “a coma” or a “vegetative state” or even “brain dead”. First things first, patients who suffer brain death are not in coma. And patients who are in coma may or may not progress to brain death.
The brain has a number of vast jobs to complete every second and is a very complex organ. The brain controls not only an individual’s thought process and voluntary movements, but it controls involuntary movements and other vital body functions. These functions include auditory, olfactory, visual and tactile senses, regulation of body temperature, blood pressure, respiration, and heart rate (although the heart can continue to beat without the brain in “autotonic response”). The brain also produces hormones to control individual organ function. A good example is the brain’s production of anti-diuretic hormone (ADH). This hormone is produced to concentrate the urine in the kidneys, thus protecting against life-threatening dehydration.
McMaster University researcher Sheila Singh and her team have discovered how glioblastoma, a lethal brain cancer, can evade treatments and kill.
The researchers found the cancer cells that survive the first round of radiotherapy or chemotherapy do so by mutating during the post-treatment minimal residual disease (MRD) or dormant state. The MRD profile of each patient was mapped using single cell sequencing to find a genetic signature that predicted how the cancer would recur in each individual.
Singh said that by mapping the MRD, researchers found that each patient had a different trajectory to their cancer recurring, potentially opening the door to future treatments tailored to each individual with glioblastoma. Singh’s team monitored five patients between 2018 and 2022.
In 2012, Nedergaard also helped to discover a network of thin tubes that collect waste fluid from brain cells, known as the glymphatic system. These tubes may drain into the outgoing cerebrospinal fluid, says Nedergaard.
The waste products of brain cells include proteins called beta-amyloid and tau that are thought to be involved in Alzheimer’s disease when they build up in excessive amounts.
In both mice and people, the SLYM also contains immune cells, so it may allow them to detect signs of infection present in the cerebrospinal fluid, says Nedergaard. “It is loaded with immune cells.”
Many neurodegenerative diseases, including Alzheimer’s.
Alzheimer’s disease is a disease that attacks the brain, causing a decline in mental ability that worsens over time. It is the most common form of dementia and accounts for 60 to 80 percent of dementia cases. There is no current cure for Alzheimer’s disease, but there are medications that can help ease the symptoms.
The Connectome and Connectomics: Seeking Neural Circuit Motifs
Talk Overview: The human brain is extremely complex with much greater structural and functional diversity than other organs and this complexity is determined both by one’s experiences and one’s genes. In Part 1 of his talk, Lichtman explains how mapping the connections in the brain (the connectome) may lead to a better understanding of brain function. Together with his colleagues, Lichtman has developed tools to label individual cells in the nervous system with different colors producing beautiful and revealing maps of the neuronal connections.
Using transgenic mice with differently colored, fluorescently labeled proteins in each neuron (Brainbow mice), Lichtman and his colleagues were able to follow the formation and destruction of neuromuscular junctions during mouse development. This work is the focus of Part 2.
In Part 3, Lichtman asks whether some day it might be possible to map all of the neural connections in the brain. He describes the technical advances that have allowed him and his colleagues to begin this endeavor as well as the enormous challenges to deciphering the brain connectome.
Speaker Bio: Jeff Lichtman’s interest in how specific neuronal connections are made and maintained began while he was a MD-PhD student at Washington University in Saint Louis. Lichtman remained at Washington University for nearly 30 years. In 2004, he moved to Harvard University where he is Professor of Molecular and Cellular Biology and a member of the Center for Brain Science.
A major focus of Lichtman’s current research is to decode the map of all the neural connections in the brain. To this end, Lichtman and his colleagues have developed exciting new tools and techniques such as “Brainbow” mice and automated ultra thin tissue slicing machines.