Astrophysics

Join a diverse, inclusive group for a supportive, encouraging meeting to develop your speaking and leadership skills based on your personal goals. We meet on the 2nd floor of the Bethesda-Chevy Chase Regional Services (BCC) Building (on the corner of Old Georgetown Rd. and Edgemoor Ln.). It is the building with flags out front and across from the bus bay for the Bethesda metro station (Red line).

[Profs and Pints DC](https://www.profsandpints.com/washingtondc) presents: **“Goddess of Spring and the Underworld,”** an introduction to the Greek goddess Persephone in her many incarnations, with Brittany Warman, former instructor at Ohio State University and co-founder of the Carterhaugh School of Folklore and the Fantastic. [Advance tickets: $13.50 plus sales tax and processing fees. Available at [https://events.ticketleap.com/tickets/profsandpints/spring-and-underworld](https://events.ticketleap.com/tickets/profsandpints/spring-and-underworld) .] Join Brittany Warman, who has earned a huge following among Profs and Pints fans by delivering fantastic talks on folklore, myths, legends, and fantasy, for the perfect event for the season: a look at the spring goddess Persephone and the many ways in which she has inspired the human imagination. The story of Hades and Persephone is one of the most famous—and most retold—episodes in Greek mythology. Persephone’s abduction, her interlude in the Underworld, and her partial return to the world above have inspired statues and webcomics, ancient cults and contemporary poetry. Thousands of years after her tale was first told, we’re still fascinated by this goddess. Brittany will discuss how Persephone’s appeal lies in her liminality in being caught between two very different worlds and lives. She represents spring, renewal, and rebirth because Earth blooms with her return, but she’s also the Queen of the Underworld. From a 21st-century perspective, she’s basically a goth girl adorned with a flower crown. We’ll also look at Persephone’s mythic roots, including their connections to the Eleusinian Mysteries. And then we’ll dive into some of the ways that Persephone has been revised and retold in recent years, from the Tony award-winning musical *Hadestown* to the webcomic *Lore Olympus* to memes and fairy tales and fashion. After all, why be just one thing when you can be the queen of both spring and darkness? (Doors: $17, or $15 with a student ID. Listed time is for doors. Talk starts 30 minutes later.) Image: From “Proserpine” (Persephone) painted by Dante Gabriel Rossetti in 1882. (Birmingham Museums Trust / Wikimedia Commons.)

Holy Cross-Words Toastmasters Club (http://1341379.toastmastersclubs.org/) is open to all. The club meets 2nd and 4th Tuesday of each month at 5:30pm via Zoom Meeting: Meeting ID: 848 0115 8880 Password: 996403 In addition, on 4th Tuesday of each month for an in-person meeting at the Professional and Community Education Center (PCEC) at Holy Cross Hospital. The PCEC is located on the first floor of Holy Cross Hospital, 1500 Forest Glen Rd, Silver Spring, MD 20910

The Lewis Smith Toastmasters is a local club under Toastmasters International. We improve our communication, public speaking and listening skills by working with others in a fun, enjoyable and supportive environment. People join Toastmasters for all sorts of reasons. Some join to strengthen their job related presentations. Others join to develop confidence speaking and listening in English. Yet others join to develop skills such as leading and conducting meetings, skills that are helpful for both volunteer work and in the work place. We meet on the second and fourth Tuesday of every month at 3820 Aspen Hill Rd Silver Spring MD 20906 (St. Mary Magdalene Episcopal Church -directly behind Aspen Hill Giant), at 7:30 PM. To learn more about our club, please visit: https://lewissmith.toastmastersclubs.org

This is a great opportunity to meet others who are new as well as those who have been around a while! Mission BBQ has some of the best BBQ in the area, served in a casual environment which honors our military and first responders. When you arrive, feel free to grab food then join us. As we're a large group, please be patient with restaurant staff and use any time in line to visit with others. Meals are in the $10-15 range. Look for GRASP table flyers and Eli's GRASP shirt to find us within the restaurant. Everyone is welcome and we can't wait to see you!

Title: Potential Applications of Negative Radiation Pressure in Astronomy, Medicine and 2WQC Date: April 19 2026 10:00 am - Noon EDT (16:00 - 18:00 CET) Abstract: While we are used to heating and pushing with light, there is also optical cooling and pulling. I will talk about negative radiation pressure, potential ways to generate it, and its novel applications, like non-ionizing medical scanners, 2WQC (two-way quantum computers) in theory solving NP problems, also potential astronomical sources and their observation. Speaker: Dr Jarek Duda is an assistant professor at Jagiellonian University. He holds degrees in computer science (PhD), mathematics (MSc) and physics (PhD). He is mainly focused on physics foundations, information theory, statistical analysis, and is known for introduction of asymmetric numeral systems.

Business Oriented Toastmasters (BOTM) is an exceptionally strong Toastmasters club in Rockville, MD. Our club has earned President's Distinguished Club status for the last thirteen years in a row. We are dedicated to helping each of our members achieve their personal public speaking and leadership goals in a friendly, supportive environment. We pride ourselves on having organized, professional meetings with strong evaluations, while having fun at the same time. Guests are always welcome and no notice is necessary. Just show up and plan to have fun. See how BOTM can help you achieve your goals. We are a diverse club with both seasoned and new Toastmasters, and all ethnic and professional backgrounds. For more information, please visit our website at botm.toastmastersclubs.org or contact us at contact-2279@toastmastersclubs.org Meeting locations: 1st Wednesday of every month in person at Faith United Methodist Church, 6810 Montrose Road, Rockville, MD 3rd Wednesday of every month via Zoom

Arlington has a planetarium called the David M Brown Planetarium. I forget about it all the time. They host a monthly event. This month's starts at 7:30pm on April 18. Let's meet up at Quincy Hall beforehand and get buzzed before we learn about the Solar System. Tickets to the planetarium show are $5. They can be bought at the door and online. The online ones aren't available yet but I'll post a link when they are. The David M Brown Planetarium is at 1426 N Quincy St, Arlington, VA 22207 right around the corner from Quincy Hall. The show is called Dynamic Earth: https://friendsoftheplanetarium.org/event-6339264

We are the Federal Center Toastmasters Club. We meet the 1st, 3rd, and 5th Thursday of each month in Hyattsville, MD, from 12 noon to 1pm. Our meetings are held at the headquarters of the CDC’s National Center for Health Statistics of the CDC. Our meetings are open to the public, though visitors must go through building security procedures. For visitors who are not U.S. citizens, we do need to pre-coordinate a first visit with our security team. Contact us at: 1260@toastmastersclubs.org. We have been a Toastmasters Club for 40 years and always welcome new members! Join us, and you will improve your public-speaking and leadership skills in a friendly, supportive atmosphere!

Title: Foundations of Localized Symmetry Mathematics Date: April 18 2026 Noon - 14:00 EST Summary: The moment you use Euclid’s definitions of points and distances in any of your mathematical axioms, all that follows is assured to produce some level of nonsensical results when applied to the foundations of physics. The reason is not complicated: Euclid’s definitions are deeply mired in accepting as a “given” the very concepts that emerge only in well-defined inertial frames, which in turn are local instances of symmetries that are always finite and context dependent. In this talk, Terry will discuss how reframing mathematics in terms of symmetries that, as in the real world, are finite, composite, and dependent on self-observation (acceleration), results in a richer and far stranger set of mathematics in absolute conservation of quantum numbers generate local and global symmetries — the opposite of Noether’s theorem — that in turn create the emergent classical phenomenal such a particles, fields, space, and time. Speaker: Terry Bollinger is a computer scientist with BS, MS, and professional degrees from the Missouri University of Science and Technology.

Join the Bitcoin District Book Club! We meet every month to explore new and exciting rabbit holes by reading books that are popular with bitcoiners. Join us for a deep dive into End Times: Elites, Counter-Elites, and the Path of Political Disintegration by Peter Turchin. In this thought-provoking session, we’ll explore the structural forces that have historically led to societal instability—and why Turchin believes we are entering such a period today. Drawing on his work in “cliodynamics” (the quantitative study of history), Turchin examines cycles of rising inequality, elite overproduction, and political fragmentation. We’ll discuss how internal competition among elites and growing public discontent have repeatedly destabilized societies—from ancient Rome to modern America—and what this might mean for the decades ahead. For those interested in macro trends, power structures, and long-term societal patterns, this book offers a compelling framework for understanding today’s increasingly chaotic world. Buy the book on [Amazon](https://a.co/d/097mab73) **Event Notes:** * Discussion Starters: We’ll kick things off with a few key questions around elite dynamics and societal cycles, but feel free to bring your own perspectives. * Future Reads: Let us know if you have recommendations for future book club selections! We’ll add them to the list posted on our website. * Afterwards: Feel free to join us at Pubkey after the meeting to hang out, continue the conversation, and grab some food! **Getting There:** * 🔴🟢🟡 Gallery Place/Chinatown + 2 min walk * Parking: Street & garage parking available nearby

**Join us in Falls Church for conversations that go beyond small talk.** Higher Grounds – Falls Church is where this growing network of gatherings began: a space for thoughtful, authentic dialogue about what matters most. Whether we’re exploring the nature of happiness, the challenges and possibilities of midlife, spirituality, culture, capitalism, parenting, or the role of art and travel in a meaningful life, every conversation is shaped by the people in the room. There’s no set leader or rigid agenda—just a shared commitment to listen as much as we speak. We start with brief introductions focused on what makes you *you* (not your LinkedIn bio), then dive straight into whatever is on people’s minds. The direction of each meetup emerges organically, making every event unique. MANDATORY: PLEASE REVIEW OUR COMMUNITY GUIDELINES IN THE GROUP DESCRIPTION. Everyone is expected to engage in respectful conversations and listen deeply as well as share. We have a zero tolerance policy of sexual harassment and hate speech. Come ready to share, reflect, and connect with others in Falls Church who are also seeking deeper conversations. **Suggested Questions: Life Stages & Transitions** 1. What did you think you'd have figured out by now that you're still completely winging? 2. When did you realize your parents' advice was for a world that no longer exists? 3. What are you finally old enough to stop pretending to care about? **Suggested Questions: Identity After the Roles** 1. Who are you when nobody needs anything from you? 2. What dream keeps resurfacing even though the "practical" time has passed? 3. How do you handle having the freedom you always said you wanted? **Suggested Questions: AI & Being Human** 1. What human experiences will AI never truly understand? 2. If machines handled all your have-to's, what would you actually do? 3. What becomes more precious as everything becomes automated? **Suggested Questions: Belief & Meaning** 1. What certainties have you given up, and what rushed in to fill that space? 2. How has knowing someone who died changed how you live? 3. What do you believe now that would shock your younger self? **Suggested Questions: The Modern Psyche** 1. What anxiety do you carry that previous generations didn't have? 2. Which of your survival strategies are you ready to retire? 3. What uncomfortable truth about happiness did it take you years to accept? **Suggested Questions: Work & Purpose** 1. When did you stop believing that your job would complete you? 2. What would you do for work if money and status weren't factors? 3. How has your definition of "making it" changed over the years? **Suggested Questions: Relationships & Connection** 1. What relationship dynamic do you keep recreating, and why? 2. When did you realize your parents were just people trying their best? 3. What kind of loneliness doesn't go away even when you're with others? **Suggested Questions: Time & Mortality** 1. What are you running out of time to say or do? 2. How differently do you spend your time knowing it's finite? 3. What will you regret not trying, even if you fail? **Suggested Questions: Society & Culture** 1. What social convention do you follow even though it makes no sense? 2. Which generation do you understand least, and what might you be missing? 3. What aspect of how we live now will seem insane in 20 years? **Suggested Questions: Personal Philosophy** 1. What rule for life did you create after learning something the hard way? 2. When did you stop believing that everyone else had it figured out 3. What paradox about life have you learned to live with?

Let’s try this popular Italian restaurant in Reynoldsburg. This is the menu: https://scaliristorante.com/#4e468054-0235-43e2-81c2-44e061341e9e

Join the CONNECTED Westerville Mastermind Group for a dynamic afternoon of B2B networking! This event is perfect for professionals looking to expand their business connections, share insights, and foster collaboration within the community. Whether you are a seasoned entrepreneur or just starting out, this event offers a valuable opportunity to exchange ideas, build relationships, and grow your network in a supportive environment. Connect with like-minded individuals, explore potential partnerships, and discover new opportunities for professional growth. Don't miss out on this chance to enhance your business network and take your career to the next level with CONNECTED Westerville Mastermind Group! We meet the 4th Monday of every month from 11am-1pm. Welcome and general networking from 11am - 11:30am with core meeting 11;30 - 12:30 and a final round of networking from 12:30 - 1pm.

Sleep in on Sundays. When you've had your fill of pajama-time, roll out and have some tasty brunch with your fellow Humanists!

Bring your Raspberry Pi, Arduino, microcontroller, or any other electronic project and join fellow electronics makers for a night of creativity and collaboration! This session is open forum to share your current projects—whether complete or in progress, it’s all interesting! Whether you’re deep into embedded systems, exploring new ideas, or just getting started, you’ll find a welcoming space to collaborate, share, and get inspired. **New to electronics or curious about tinkering?** You’re absolutely welcome. If you’re a beginner and want to experiment, I’ll have a couple of starter kits available so you can try things out—whether that’s blinking your first LED, putting something on a display, or experimenting with simple sensors. No pressure and no experience required—just an interest in learning and building. While we continue to pursue a more permanent venue for this Meetup, we’ll be using public library facilities based on availability. This session will be at the Worthington Park Library in the Olentangy Meeting Room.

ASH is Atheists, Skeptics and Humanists of First Unitarian Universalists of Columbus Ohio TBD Snacks are usually available, and you are welcome to bringing something to share!

It’s time to take control of your mental health. How do you get rid of stress, anxiety and uncertainty? These emotions are buried deep in your reactive mind. Find out what the reactive mind is, and in the process find yourself. Here is the secret of being positive and free: Thinking positively is not enough. You also have to get rid of the negative thinking. Your mind is like a garden. You can plant many beautiful flowers in it, but if you don't get rid of the weeds when you plant your flowers, the weeds will soon take over the whole garden. A positive thought is like a flower in your mental garden, and a negative thought is like a weed. You cannot expect to have a positive mindset if you continue to have negative thoughts dwelling and growing there. So, how do you get rid of the negative thoughts? That's what this Meetup is all about. Attend this local meeting and find out! The Meetup event will be led by a consultant who had helped many people live happier in life. Be sure to click on the red "Attend" button below to come to this local event. We look forward to seeing you there. This group is created by the Dianetics & Scientology life improvement center.

Let’s meet and share our thoughts about Carson McCullers’ novella, The Ballad of The Sad Café.