I have a BS in Information Sciences from UW-Milwaukee. I've helped manage Physics Forums for over 22 years. I enjoy learning and discussing new scientific developments. STEM communication and policy are big interests as well. Currently a Sr. SEO Specialist at Shopify and writer at importsem.com
Standard cosmological models are classified by spatial curvature into three broad types: open, flat, and closed universes. These correspond to negative, zero, and positive spatial curvature respectively, and each case has distinct implications for the geometry and global volume of space. Open, Flat, and Closed Universes In the simplest Robertson–Walker models the three cases can…
Definition/Summary The Einstein Field Equations (EFE) are a set of ten interrelated differential equations that form the core of Einstein’s general theory of relativity. These equations describe how matter and energy determine the curvature of spacetime, providing a mathematical framework to relate spacetime geometry to its energy-matter content. Mathematically, the EFE relate the Ricci curvature…
PF Advisors: How AI Will Affect STEM — Part 3 We asked our PF Advisors, “How do you see the rise in AI affecting STEM in the lab, classroom, industry, and everyday society?” We received so many great responses we needed to split them into parts. These are the first responses for part 3. Read…
We asked our PF Advisors: “How do you see the rise in A.I. affecting STEM in the lab, classroom, industry, or in everyday society?” We received so many great responses that we split them into parts. This is Part 2. Read Part 1 here. Enjoy! gleem — overview AI: Maybe not quite ready for prime…
We asked our Physics Forums (PF) Advisors: “How do you see the rise of AI affecting STEM in the lab, classroom, industry, and everyday society?” We received many thoughtful replies and are publishing them in parts — here are the first responses. Enjoy! Community responses Ranger Mike If past trend forecasting is any guide, I…
Today we get to know a little more about Engineering Mentor jrmichler! Tell us a bit about your education and academic years Two years college (UW-Madison) in electrical engineering. Burned out (two semesters of 21 credits, tired of poverty, needed to think some things through), dropped out, joined US Air Force. Four years later, had…
Time to test your science knowledge with a fun 10 question quiz with random questions across all sciences. Difficulty is easy to medium. As always, post your score in the comment thread. Enjoy! Comment Thread
What is a limit? In mathematics, a limit describes the behavior of a function or sequence as its input approaches a particular value. Limits are a cornerstone of calculus and are used to define continuity, derivatives and integrals. Key aspects of limits: Definition: The limit of a function or sequence as it approaches a specific…
Experts weigh in: Most revolutionary technologies and discoveries in the next 20 years We asked our Physics Forums science advisors, “What technology or scientific discovery will be the most revolutionary within the next 20 years?” Below are their responses, edited for clarity and readability while preserving each contributor’s original voice. Demystifier “Machine learning will be…
Don’t forget to read Part 1 of this interview. Peak Oil and Future Energy Sources Professor Kaku, what do you think of “peak oil”? How serious is it, and what alternative sources of energy do you think will best provide the world’s needs in the coming decades after fossil fuels start to decline (whether it…
We are happy to present this archived interview with Dr. Michio Kaku, conducted in 2004. Michio Kaku is an American theoretical physicist, futurist, and popularizer of science. He is a professor of theoretical physics at the City College of New York and the CUNY Graduate Center. Kaku has written several books about physics and related…
Time to test your inventions, inventors and patent knowledge. As always there is no prize, so try without Google. Post your score in the comment thread. Good luck!
Tell us about your school years? Part of my story is sad but common. I was a poor student. I didn’t pay attention, and I never did homework even once; until one day when it all flipped. That was the day I first learned about differential equations. Diffy-Q was so much fun, that it completely…
Give us an executive summary on bhobba I was born in Toowong Brisbane Australia 17/11/1955, and was raised in suburbs around Toowong – Toowong itself, Taringa and Indooroopilly. I went to 3 schools: Taringa State School, Toowong High and Indooroopilly High. I now live in Redland Bay Queensland Australia. It is about halfway between Brisbane…
We asked our PF Advisors to tell us what their favorite science or math blog is (other than PF Insights). We also have a physics blog list here. Here are their responses…
Physics Forums is pleased to introduce Niels Tuning. He’s a physicist working as the Run Coordinator for the LHCb experiment at CERN. Apart from the questions below you can learn more about him at his website. Niels Tuning also has an active Twitter account here. About Niels Tuning Already as a child I was fascinated…
We asked our PF Advisors to tell us what academic advice would you tell your 18 year old self. Here are their responses… PF Advisors’ Academic Advice Thanks & Next Steps Thanks to all the PF Advisors that shared their academic advice. We have more questions for them in the near future. Stay tuned for…
We asked our PF Advisors to tell us their most memorable or influential textbook and why. Here are their responses… PF Advisors’ Favorite Textbooks Thanks & Next Questions Thanks to all the PF Advisors that shared their favorite textbook. We have more questions for them in the near future. Stay tuned for another “Ask the…
Adam Becker is an astrophysicist and science writer whose first book, What Is Real?: The Unfinished Quest for the Meaning of Quantum Physics, has just been published. Give us some background on how you got interested in physics and formative youth experiences I don’t remember a time when I wasn’t interested in science. Some of…
Clifford V. Johnson is a professor in the Physics and Astronomy Department at USC. He says, “I mainly work on (super)string theory, gravity, gauge theory and M-theory right now, which lead me to think about things like space-time, quantum mechanics, black holes, the big bang, extra dimensions, quarks, gluons, and so forth.” Clifford V. Johnson…
Let’s see how well you know your science book authors. Some are classic, some modern! Don’t forget to post your score in the comment thread linked at the bottom.
The 2017 August Eclipse really was something special. Fortunately Physics Forums has great photographers and snapped some remarkable shots. Here are a few highlights.
Interview: From Biology to Programming, Sysadmin, and Life in New Mexico What got you interested in biology? I was an amateur naturalist as a kid. I kept collections of all sorts and a small menagerie — much to my mother’s dismay when an anole got loose in the basement. I graduated from college with a…
Time to test your scientist photo recognition skills! As always please post your score in the comment thread at the end. Ready for your next quiz? How well do you know about inventions?
Please give us a bit of background into your educational and professional life. I’m a public school kid through and through. After going to the local high school where I grew up in Westford, Massachusetts, I attended Michigan State University to earn a bachelor’s degree in astrophysics (with several extra classes in Computer Science). From…
Video Q&A: Fraser Cain (Universe Today) Special thanks to Universe Today founder Fraser Cain for this fascinating video Q&A. All questions were provided by members of Physics Forums. The full question list appears below the video. Read the next interview with astronomer Pamela Gay.
We are pleased to introduce Sabine Hossenfelder. Sabine is a theoretical physicist at the Frankfurt Institute for Advanced Studies. She also authors the popular physics blog Backreaction. Interview: Sabine Hossenfelder Reading your blog over the past 6 months or so, one gets a feeling that your views about (particle) dark matter versus modified gravity have…
We have an amazing count of over 320 Insights published at Physics Forums. Now we test to see how much you remember from some of them. If you need a hint feel free to read the corresponding Insight which is linked at the end of the question. Good Luck and remember to read future Insights…
Since the mid 20th century NASA has been a force in aerospace research and programs. Let’s find out just how much you know about it’s history, programs and research. Don’t forget to post your score in the forum thread. No prizes, so don’t Google it. :) Ready for your next quiz? How well do you know…
Give us a little background on Jim Hardy Born and raised in Miami, Florida, to parents with roots in Springfield, Missouri. So at heart I’m a small‑town Midwestern fellow. Miami was small in the 1950s, but it became cosmopolitan and outgrew me. I spent a career working in the nuclear plant south of Miami, so…
Give us a brief history on stevendaryl I was born and raised in the American South, mostly living in Georgia. It’s a Southern tradition, for some reason, for kids to be called by their middle name, so my friends call me “Daryl” even though my first name is “Steven”. I grew up in a family…
Stephen Hawking has been a giant in the science world for decades. He has been a accessible figure with his willingness to reach out to the public in various ways. Time to see how much you know about him. There are no prizes so no Goolging! Post your score in the discussion area. Ready for your…
For those who don’t know the great David Hestenes, he is the inventor of the geometric algebra formalism of physics. Here we go! 1) What is the best application of geometric algebra in theoretical physics that you can think of? In other words, what application shows the power and elegance of geometric algebra best? The…
We are pleased to share with you an interview with PF Science Advisor and one of our founding members: DrChinese Who is DrChinese and share some early experience that got you interested in science. I am a Dallas, Texas, USA boy, now married with grown kids. I got very interested in science at a private…
We are pleased to introduce David J. Griffiths, one of the most successful physics textbook authors. Odds are if you studied physics in college, you’ve used one of his textbooks. We are honored to share some of his insights on quantum mechanics and the academic world. Please give us a background on your educational background…
Summer is almost over, but the fun doesn’t have to stop! Take a look at the photos below and see if you can identify them. Post your score in the comment section. Good luck!
Give us a little background on yourself? I was born in Washington DC, grew up in Texas, bachelor’s in physics from Harvard in 1978 but found a career in system software instead. Son of two law professors and grandson of a third, raised a Quaker although it didn’t stick, keep a small fleet of well-rusted…
We are pleased to introduce Sean Carroll. Sean Carroll is a theoretical physicist at Caltech specializing in cosmology and quantum mechanics. He has a new book, The Big Picture, which addresses “On the Origins of Life, Meaning, and the Universe Itself.” Key Points Sean Carroll grew up near Philadelphia and studied at Villanova University. His…
For ages it has been Earth’s little sister. Find out just how much you know about the Moon and our relationship with it. Please post your score in the comment section. Ready for your next quiz? How well do you know about NASA?
We are pleased to introduce Peter Krautzberger. Peter is a manager for MathJax, the technology behind the display of equations on Physics Forums. “The core of the MathJax project is the development of its state-of-the-art, open source, JavaScript platform for display of mathematics.” Please give us a bit of background on yourself I was born…
DrClaude is a mentor at Physics Forums! What brought you to Sweden from Canada? Life, the Universe, and Everything. While in Canada, I was offered the opportunity to do part of my studies in France. After my Ph.D., I stayed in France for postdoctoral work. I tried getting an academic position in France, but it…
PeterDonis is a Physics Mentor at Physics Forums. About PeterDonis I have been interested in science since childhood. I hold two degrees in Nuclear Engineering (focused on fusion rather than fission), which are effectively degrees in plasma physics. I was also Navy ROTC and served six years in the U.S. Navy after graduation. After that…
Please give us a bit of background on your life and professional experience Life: Born and educated in Italy; I then spent 10 years in the United States and 15 in France. I came to physics late: before that I was more into hippie dreams and even trying to overthrow the Italian government. Professional: In…
Have you been keeping up with reading each PF Insight? Let’s find out! Every question’s answer can be found in a PF Insight. Hint links are included if you need help. Be sure to post your score in the comment area.
We are pleased to introduce Theoretical Physicist and Physics Forums member Garrett Lisi, an experimental surfer who developed a distinctive approach to a theory of everything. Read on for an interview covering his early life, E8 work, and life in Maui. Tell us a little about growing up in San Diego I grew up in…
Can you give us a brief history of berkeman? I grew up in a military family (my dad was an Army colonel), so we moved all over the place when I was a kid, finally settling in Calistoga in the northern part of the Napa Valley, California, for my high school years. Being a military…
Give us a brief history of Borek Note: text below is of a negative pedagogical value, don’t read it if you are younger than 20, attending school or still naïvely hoping for the best. I was born half a century ago, in a galaxy far, far away. So far away our laws were all shifted…
This is a new Interview category for Insights. While I line up some great new interviews I’ll be migrating some previous mentor interviews. ZapperZ is a staff emeritus at Physics Forums Can you give us a brief history of ZapperZ? Without reveal things that are answers to a few of the security questions to my accounts,…
Think you know your famous science quotes? Let’s find out in this 12 question quiz. There are no prizes, so it doesn’t pay to Google. Try your best on your own. Report your score in the comment area at the bottom. Good luck!
Let me introduce you to Andy Resnick, a long time Science Advisor at Physics Forums. Tell us a little bit about how you developed an interest in biophysics That’s a good question, and I’m not sure how to answer. I’ve worked in the ‘in-between space’ for many years- for example, optics is in-between physics and…
This is a new Interview category for Insights. While I line up some great new interviews I’ll be migrating some previous mentor interviews. Doc Al is a physics mentor for Physics Forums Can you give us a brief bio? Okay. It was never easy for me. I was born a poor black child. I remember…
This is a new Interview category for Insights. While I line up some great new interviews, I’ll be migrating some previous mentor interviews. About Russ Watters Russ Watters is an engineering mentor for Physics Forums. Brief bio I’m 37, I live outside of Philadelphia and I have a BS in Mechanical Engineering from Drexel University….
Winter is coming. First day of Winter is December 22nd. Time to learn a bit about a substance that the northern regions will encounter. Don’t forget to share your score in the comment section. Ready for your next quiz? How well do you know about the ice planet Pluto? 1. What is Ice? Ice is…
Pluto has been in the news quite a bit these past several months. Let’s see if you’ve been paying attention. Feel free to share your score in the comments section. When finished head over to our Pluto Flyby forum thread for the latest news. Ready for your next quiz? How well do you know ice?
What is evolution? In every field of scientific endeavor there sometimes comes a quantum shift in knowledge, a grand denouement that changes how we see the world. In physics we have Newton’s laws, Einstein’s Relativity and Quantum Mechanics; in biology we have the discovery of DNA and Darwinian evolution. Why evolution matters It’s hard to…
Eugene Cernan: Last to Walk on the Moon On December 11, 1972, astronaut Eugene Cernan became the last person to walk on the lunar surface, marking the conclusion of NASA’s Apollo missions. This pivotal chapter in space exploration saw humanity push the boundaries of science and engineering to unprecedented levels. The Apollo program remains a…
One of the great heavy weights of history. How much do you really know about him? Let’s find out! “To myself I am only a child playing on the beach, while vast oceans of truth lie undiscovered before me.” – Isaac Newton Ready for your next quiz? How well do you know Albert Einstein?
News of the LHC progress has dazzled scientists and hobbyists alike. It’s now time to show just how much you know about the operation. Please share your results Ready for your next quiz? How well do you know about the Periodic Table of Elements? 1. What is the Large Hadron Collider (LHC)? The Large Hadron…
These are some of the best physics blogs, updated regularly, written by some of the top minds. The feeds are updated on page refresh, so bookmark this page and you’ll have a quick overview of all the blog’s latest entries each time you visit here. We also asked our community advisors which physics blogs they recommended….
The periodic table is something we all are made aware of early in schooling, but have you really looked at it closely and learned about its lesser-known facts? Let’s find out! Ready for your next quiz? How well do you know about the LHC? 1. What is the Periodic Table? The Periodic Table is a…
Richard Feynman is one of the most popular and highly regarded physicists of all time. You think you may know him, but do you? Let’s find out by taking this quiz! Ready for your next quiz? How well do you know Stephen Hawking? 1. Who was Richard Feynman? Richard Feynman was an American theoretical physicist…
Albert Einstein is arguably the most famous scientist of all time, but how much do you actually know about him? Let’s find out by taking this quiz! No prizes, so no Googling. (post your honest score in the discussion thread) Ready for your next quiz? How well do you know Isaac Newton? 1. Who was…
*This Insight is intended to have a logical basis but not to be taken as purely factual or legal advice. Key Points Outer Space Treaty does not provide clear guidance on the legality of satellite-based lasers. One should apply to the ITU when planning a telecommunications satellite. Do not interfere with the remote sensing activities…
Bioethics Key Points Worrying about the future now means recognizing advances in technology, such as genetic engineering, that have already arisen. The standard of health is not fixed; it will fluctuate depending on perceptions of different biological variations that may emerge in the human species. We must be careful using new technologies and understand their…
Eclipse Viewing Key Points Never view the Sun with the naked eye for any length of time; doing so can cause irreversible eye damage or blindness. Only totality during a total solar eclipse is safe to view with the naked eye. All other phases must be viewed using proper solar filters or an indirect method….
Star Fate: From Birth to Black Holes Stars form in vast clouds of gas and dust called nebulae. Over time gravity pulls material together until the core becomes hot and dense enough for nuclear fusion to begin. From that point on, a star’s long-term fate is determined primarily by its mass, which sets its lifetime…
Discussing science online can be a frustrating experience when no quality controls are in place—which is often the case. As part useful reference and part entertainment, PF has put together a list of common attributes associated with dubious scientific discussion. Next time you’re in a debate, check this list to see whether the participants are…
Physics of Hand-to-Hand Combat Hand-to-hand combat (often abbreviated H2H or HTH) refers to fighting at very close range, usually without weapons. It includes self-defense, sport, and military contexts where encounters happen inside arm’s reach. Effective techniques exploit basic physics: getting the right force to the right place at the right time through timing, balance, and…
Meet a Mentor is a biweekly (twice a week) series to help you get to know your wonderful Mentors better. Constructive questions and comments are welcome! Today we meet: Integral Can you give us a brief bio? I am a 2nd generation Oregonian born smack in the middle of the 20th century. My dad came…
Meet a Mentor is a series to help you get to know your wonderful Mentors better. Constructive questions and comments are welcome! Today we meet: D H Give us a brief history of D H I spent my childhood in Minnesota, the first nine years in Minneapolis and the last nine on a farm. I…
Meet a Mentor is a weekly series to help you get to know your wonderful mentors better. Constructive questions and comments are welcome! Today we meet: George Jones Give us a brief history of George Jones. On my mother’s side, my roots in Canada have been traced back to the late 1600s; on my father’s…
Meet a Mentor is a biweekly (twice a week) series to help you get to know your wonderful Mentors better. Constructive questions and comments are welcome! Today we meet: Evo Can you give us a brief bio? I’ve been in love with science as long as I can remember. As soon as I began to…
Meet a Mentor is a fun series to help you get to know your wonderful Mentors better. Constructive questions and comments are welcome! Today we meet: Lisab Give us a brief history of Lisab I didn’t follow the usual education route. I dropped out of school in about 8th grade to hang out with my hoodlum…
Meet a Mentor is a fun series to help you get to know your wonderful Mentors better. Constructive questions and comments are welcome! Today we meet: @Ryan_m_b Give us a brief history of Ryan_m_b I’m in my mid-twenties, spent most of my life living in a small town on the border of the countryside, but…
Meet a Mentor is a series to help you get to know your wonderful Mentors better. Constructive questions and comments are welcome! Today we meet: Mark44 How did you become interested in mathematics? Along about 4th grade I came across an algebra textbook that really fascinated me, with all of its x’s and y’s, and…
Meet a Mentor is a weekly series to help you get to know your wonderful Mentors better. Constructive questions and comments are welcome! Meet the Mentor: jtbell Can you give us a brief history of jtbell? I went to a small, liberal-arts college in a Midwest village in the US. There were only three physics…
Meet a Mentor: DaleSpam Meet a Mentor is a fun series to help you get to know your wonderful Mentors better. Constructive questions and comments are welcome! About DaleSpam Today we meet: DaleSpam. Give us a brief history of DaleSpam I have moved around a decent amount during my life: Arizona, Indiana, Colorado, Texas, Michigan,…
Meet a Mentor is a fun series to help you get to know your wonderful Mentors better. Constructive questions and comments are welcome! Today we meet: @Chestermiller Give us a brief history of Chestermiller Born January 1942 in Brooklyn, NY. Samuel J. Tilden High School, graduated June 1959 (Captain, Math Team). Cooper Union for the…
[CONTENT] Key Points Evolution is a scientific theory supported by multiple independent lines of evidence. In science, the term “theory” denotes a well-tested explanatory framework, not a mere guess. Evolution and religion do not necessarily conflict; many religious people accept evolution. The second law of thermodynamics does not rule out evolution because Earth is not…
Evidence for Evolution If you’re new to the topic, these primers provide helpful background: What is Evolution: A Beginner’s Guide What Is Evolution and How Does It Happen? Evolution FAQ Evolution Key Points The fossil record shows broad trends over time, including changing forms and increasing similarity to many modern lineages, consistent with common ancestry….
Digital Modeling Key Points Digital Signal Processing (DSP) emerged in the mid-1970s, enabling musicians to simulate acoustic spaces and reproduce many classic effects in digital form. For many years, guitar tone was largely limited by the physical gear you owned; chasing specific sounds often required expensive vintage equipment. Modern microprocessors and improved algorithms now allow…