A visual way of thinking about General Relativity

 General relativity (GR) is Einstein's masterpiece. It also is the modern theory of gravity, including what causes gravity - the curvature/warping of the spacetime fabric of the universe. Here is an interesting video with a visual way of thinking about what this means, as it is quite abstract for our 3-D brains to imagine a 4-D universe! Thanks to Luca for finding and sharing this. 

Shortest time period ever measured - check this out!

 How much time does it take light to pass a hydrogen atom??? Keep in mind that the ground state orbital for hydrogen is 0.53 Angstroms, and the speed of light is the fastest there is, 300,000,000 m/s. Do the math, and obviously it does not take much time for this to happen. It has been measured, and is 247 zeptoseconds! This might be the only time in your life you even see the prefix 'zepto,' which is 10^-21!! Wow!! 

Check out the article that explains how scientists did this. 

A new state of matter - Time Crystals

 Thanks to Jack B. for finding this article on Time Crystals, a strange form of matter found in a quantum computer of all places! 

This is a material that is switching back and forth between two different quantum energy states when created in a very cold environment. There is no loss or gain of energy externally, and effectively there is no increase in entropy of the system. It is described to be like a pendulum that never stops swinging; there is no change or randomness in its switching behavior as long as it is in this strange state. 

First all-civilian space crew goes up with SpaceX

 An all-civilian crew, with NO professional astronaut, is up in orbit on a SpaceX vehicle! Pretty cool! 

First group of Top 50 Finalists for the Global Student Prize!

 If you would like to learn about what kind of impact on national and global levels students in high school and college can have, check out the first cohort of Global Student Prize Top 50 finalists! One of these students will be named a winner and receive $100,000 to put towards their missions and organizations. 

If you would ever like to become involved in something that addresses a passion of yours, or even start an organization to address issues of concerns, IT IS POSSIBLE and even as a teen YOU CAN MAKE A DIFFERENCE AND AN IMPACT FOR THE BETTER!!!!

Also announced is the 2021 group of Top 50 Global Teacher Prize Finalists, one of whom will win a $1 million award in November. 

Water in Crisis around the world, and check out UN SDGs

 There is a major issue that just a decade or two ago people were beginning to worry about, and now seems to be here at an accelerating pace - water shortages. 

With population growth and climate change, more regions of the world are suffering changes in rain and snow falls, extended droughts, and changes in agriculture. Water is in shortage in more locations around the world, and perhaps Americans will begin to realize this (although those living in the west and southwest are already living it) as rivers and watersheds in the US begin to dry up. 

Check out CNN's feature on the Colorado River, the most important river running through the southwest. In fact, just one week ago the federal government declared a water shortage for the Colorado River for the first time ever. Parts of the Mideast are becoming uninhabitable. The path much of the world, certainly coastlines, can and will need to take for fresh water is desalination (if you can develop a cost-effective, large-scale process for this, you will be among the billionaire crowd and will help hundreds of millions/billions of people in the process). This has already started in very limited locations, but here is a 2015 article outlining the thinking for the past decade. 

Having water, the most basic consumable humans and all life as we know it need to survive, is, of course, one of the great problems and issues the world faces, and is highlighted by the United Nations in its list of 17 Sustainable Development Goals (SDGs). These will be referred to on occasion, and we will have a 2nd quarter project built around whichever goal is most interesting/important to you! 

Former life: Particle detectors over the years

 A good Science News article about particle detectors, which allow us to figure out what we are all made of! There are hundreds of particles, most of which are combinations of the six quarks! We'll get into this a bit in classes!! Here is the CDF detector from Fermilab; I helped build, maintain and run this thing. I'm still impressed these most complicated machines and experiments even work! 

A Study Effectively Confirms Energy Imbalance of the Earth Due to Humans

 A Princeton study confirms the growing energy imbalance of the earth is due to humans, and not natural processes. By 'imbalance' we mean there is no longer an equilibrium between the energy entering the earth's atmosphere and the energy that is re-radiated back into space. The warming of the earth is the result of the imbalance - caused primarily by greenhouse gases trapping more of the energy that should be making it back into space. 

Satellite data over two decades, then fed into numerous independent computer models for climate, all confirm there is no set of natural processes that have occurred over this time period to account for the warming. Only by adding in human contributions does one even approach the observed imbalance. This is but one more of many studies that all reach this conclusion that global warming and the climate change that results is due to humans, as it has a less than 1% uncertainty in these results. 

A pretty good list of how we can be happy and successful - from Michael Jordan

 I grew up watching Michael Jordan play basketball, from college through his entire professional career. Many believe, myself included, he is the best, most complete player of all-time, but of course this sort of thing is subjective and simply fun to think about...and it is not the thing to focus on. 

Instead, remember not to put anyone on a pedestal. Every human being is a flawed individual, we all make mistakes, and we all have struggles to overcome. Having said that, what we can get from the 'greats' in any field are insights and suggestions for how to approach life and find happiness and success (personally I think success in life is achieved when one is happy and healthy, whatever that means to each individual based on our own passions and joys in life...do what you love, that doesn't hurt others!). 

Take this for what it's worth to you, but here are 10 things MJ did that worked for him, and kept him motivated and the fire lit inside to always want to use each day to make himself better. For anyone who has ever read or thought about personal growth methods, this follows along with tried and true methods many have used in some form over centuries of time...some of these could work for YOU, too! 

Point is, each of us can always improve and try to become a better human being every single day of our lives by helping ourselves and others, and that's a pretty cool realization to reach!!  

What is Electrical Resistance?

 Every electrical device you have used has something called electrical resistance. If you've noticed electrical devices get warm - perhaps a calculator or cell phone or a stereo or computer that's been on - that heat is the sign of electrical resistance. 

When electric current flows through anything, where the current is a flow of electrons, those electrons collide with atoms within the lattice of the material. Even good conductors like copper wire and gold, will get warm...there are no perfect materials, and atoms get in the way of the flowing electrons! 

This video will use a simulation to get some images in our heads as to what happens at the micro-level. And also remember this: in mechanics, all collisions have some loss of kinetic energy. So every electron loses KE in a collision to that atom, and the atom then vibrates in place a little faster. From chemistry, we know that the temperature of a material depends on the average KE of its atoms and molecules - so if there is an increase in vibrational KE of the atoms of a material, it feels warmer to us! 

Materials that create few collisions for the electrons in the current have low resistance (small numbers of ohms), and if there are a lot of collisions there is a higher resistance (larger number of ohms, the unit of resistance). 

See another video for how we handle multiple resistors in circuits, in combinations of series and parallel, that we need for circuit analysis.