Physics

At speeds we can scarcely fathom, particles invisible to our senses collide with one another—in a startling moment, all existence becomes possible.

Theoretical particle physics seeks to understand the seemingly miraculous meaning of this moment of matter in motion and the principles governing the basic building blocks of nature itself. By observing elementary particle collisions, physicists seek support for a grand unified field theory and an insight into the nature of how the four fundamental forces—gravity, electromagnetism, and the strong and weak nuclear forces —came into existence when the universe was new.

LTU faculty and students are engaged in research into the phenomenological aspects of particle physics. Examining data from collider experiments such as those at LHCb (in Europe) and Belle II (in Japan), they look to add depth and nuance to our understanding of heavy quarks. As these quarks decay, the information within them becomes transparent, and this process reveals new, undiscovered particles. This research represents an exciting and potentially revelatory excursion past the limits of human knowledge.

The origin of the universe, redux.

Subatomic particles, brought together under tremendous pressure at extreme temperatures, recreate the first form of matter that existed in the universe moments after the Big Bang. Relativistic nuclear collisions allow physicists to create and study this “new,” yet old, form of matter called Quark-Gluon Plasma (QGP). Formed by a combination of quarks and gluons, QGP provides one of the only avenues to study the strong nuclear force, which is one of the four fundamental forces binding the universe together.

Students and faculty are actively engaged in studying the results of the relativistic heavy ion collider and the large hadron collider, in which particles collide at nearly the speed of light to create QGP. Their research goal is to characterize the properties of QGP and learn more about this fundamentally strong force. To do this, they apply principles of quantum mechanics, statistical and thermal physics, relativity, and hydrodynamics, supported by cutting-edge numerical methods for solving equations and analyzing large data sets.

The earliest humans sought order and meaning in the movement of the stars across the celestial firmament. They asked questions about the beginning of the universe and its eventual end. Their speculations mixed science with storytelling and measurement with myth. The methods have evolved, but the questions remain. Astrophysics supplies modern answers to these ancient inquiries.

Astrophysics is concerned with the origin, evolution, and end of the universe. It employs physics and chemistry to explain the formation of stars and other natural objects in space. Employing powerful tools for observation and analysis, including cutting-edge computer technology and sophisticated programs, allows LTU students to examine astonishing natural phenomena such as light orbiting a black hole. Our own solar system provides a rich assortment of different orbital motions, conjunctions, and eclipses for students to examine and explore.

Classical physics is rooted in the analysis of the interactions between atoms and other subatomic particles to determine their influence on the properties of physical phenomena.

Condensed matter physics (once known as Solid-State Physics) is the modern iteration of this classical field. It is the microscopic and macroscopic study of physical objects in a solid or amorphous state. The practical applications of this field are seen in the developments of transistors, optical fiber, magnetic storage media, liquid crystal displays, and solid-state lasers.

Physicists specializing in CMP have a plethora of options when it comes to career opportunities. They can continue their academic studies, pursue careers in industrial research, design magnetic “levitation” systems for high-speed rail and mass transit, create electronic filters needed for broadcasting, or improve the capacity for magnetic research imaging—the opportunities are limitless.

Today’s science fiction may soon become science fact. The study of optical forces represents an exciting and new frontier of science that potentially holds many secrets to revolutionary technological advancement.

Optical forces find applications in various areas, including optical tweezers to handle lice cells and trapping atoms to study quantum entanglement. Students are regulating optical forces based on laser focus sizes, micro and nanoparticle sizes, and particle materials. This meticulous research holds profound implications for a radically new, all-encompassing way of understanding the relationship between matter, energy, and force.

Since the creation in 1981 of the scanning tunneling microscope, scientists have delved into the fascinating world of portraiture on the nanometer scale—the science and art of perceiving the infinitesimal.

Atomic Force Microscopy (AFM) is a high-resolution microscopy technique that maps the surface features of objects by detecting the contact forces between them. Among its diverse benefits is the core ability to study the structure and properties of the tiniest particles.

Used to image almost any type of surface, measure and localize forces, topographic imaging, and measure mechanical properties, AFM can be used to solve problems in molecular engineering, polymer chemistry, molecular biology, and medicine.

Biophysics is an interdisciplinary field that explores complex biological systems at the molecular and cellular levels by integrating principles from physics, chemistry, and biology.

At LTU, the study of liposomes – lipid-based vesicles – provides valuable insights into advanced biophysical processes. These highly versatile systems can be engineered to interact with a variety of proteins and biological targets. By varying the types of lipids used in their formation, researchers can manipulate liposomes’ size, shape, and properties such as charge, fluidity, and concentration. This adaptability enhances their ability to interact effectively with specific biological membranes. Employing quantitative fluorescence techniques and statistical analysis, faculty and students investigate liposomes in the context of biological membranes and fundamental biophysical processes, including membrane fusion and protein-lipid interactions.