Digital Commons Network^™

Poincaré Invariance And The Unruh Effect, Alexandre Deur, Stanley J. Brodsky, Craig D. Roberts, Balša Terzić

Physics Faculty Publications

In quantum field theory, the vacuum is popularly considered to be a complex medium populated with virtual particle + antiparticle pairs. To an observer experiencing uniform acceleration, it is generally held that these virtual particles become real, appearing as a gas at a temperature that grows with the acceleration. This is the Unruh effect. However, it has been shown that vacuum complexity is an artifact produced by treating quantum field theory in a manner that does not manifestly enforce causality. Choosing a quantization approach that patently enforces causality, the quantum field theory vacuum is barren, bereft even of virtual particles. …

Real-Time Estimators For Scattering Observables: A Full Account Of Finite-Volume Errors For Quantum Simulation, Ivan M. Burbano, Marco A. Carrillo, Rana Urek, Anthony N. Ciavarella, Raul A. Briceno

Physics Faculty Publications

The real-time correlators of quantum field theories can be directly probed through new approaches to simulation, such as quantum computing and tensor networks. This provides a new framework for computing scattering observables in lattice formulations of strongly interacting theories, such as lattice quantum chromodynamics. In this paper, we prove that the proposal of real-time estimators of scattering observables is universally applicable to all scattering observables of gapped quantum field theories. All finite-volume errors are exponentially suppressed, and the rate of this suppression is controlled by the regulator considered, namely, a displacement of the spectrum of the theory into the complex …

Recent Progresses In Few-Nucleon Structure And Dynamics In Chiral Effective Field Theory, Laura Elisa Marcucci, Alex Gnech, Michele Viviani

Physics Faculty Publications

The most recent progresses made within the framework of chiral effective field theory for few-nucleon structure and low-energy reactions are here presented. In particular, for the A = 2 sector, the study of muon capture on deuteron is reviewed. Then, the results obtained using the Hyperspherical Harmonics ab-initio method for the 4He monopole form factor and the ³He(n^→ ,p)³H parity-conserving asymmetry are described.

Proton Transparency And Neutrino Physics: New Methods And Modeling, Clas Collaboration, S. Dytman, M. Betancourt, N. Steinberg, L. B. Weinstein, A. Ashkenazi, J. Tena-Vidal, A. Papadopoulou, G. Chambers-Wall, J. Smith, P. Achenbach, J. S. Alvarado, M. J. Amaryan, H. Atac, L. Baashen, N. A. Baltzell, L. Barion, M. Bashkanov, M. Battaglieri, F. Benmokhtar, A. Bianconi, A. S. Biselli, M. Bondi, F. Bossù, S. Boiarinov, K. -Th. Brinkmann, W. J. Briscoe, W. K. Brooks, S. Bueltmann, V. D. Burkert, T. Cao, R. Capobianco, D. S. Carman, J. C. Carvajal, P. Chatagnon, V. Chesnokov, H. Chinchay, G. Ciullo, P. L. Cole, M. Contalbrigo, A. D'Angelo, N. Dashyan, R. De Vita, M. Defurne, A. Deur, S. Diehl, C. Djalali, R. Dupre, H. Egiyan, A. El Alaoui, L. El Fassi, L. Elouadrhiri, M. Farooq, S. Fegan, I. P. Fernando, A. Filippi, G. Gavalian, G. P. Gilfoyle, R. W. Gothe, L. Guo, K. Hafidi, H. Hakobyan, M. Hattawy, F. Hauenstein, T. B. Hayward, D. Heddle, A. Hobart, M. Holtrop, Yu-Chun Hung, Y. Ilieva, D. G. Ireland, E. L. Isupov, H. Jiang, H. S. Jo, S. Joosten, M. Khandaker, A. Kim, F. J. Klein, V. Klimenko, A. Kripko, V. Kubarovsky, S. E. Kuhn, L. Lanza, P. Lenisa, D. Marchand, V. Mascagna, D. Matamoros, B. Mckinnon, T. Mineeva, M. Mirazita, V. Mokeev, C. Munoz Camacho, P. Nadel-Turonski, T. Nagorna, K. Neupane, D. Nguyen, S. Niccolai, M. Osipenko, L. L. Pappalardo, R. Paremuzyan, E. Pasyuk, S. J. Paul, W. Phelps, N. Pilleux, S. Polcher Rafael, J. W. Price, Y. Prok, T. Reed, J. Richards, M. Ripani, J. Ritman, A. A. Rusova, S. Schadmand, A. Schmidt, R. A. Schumacher, M. B. C. Scott, Y. G. Sharabian, E. V. Shirokov, S. Shrestha, N. Sparveris, M. Spreafico, S. Stepanyan, I. Stakovsky, S. Strauch, J. A. Tan, M. Tenorio, N. Trotta, R. Tyson, M. Ungaro, D. W. Upton, S. Vallarino, L. Venturelli, T. Vittorini, H. Voskanyan, E. Voutier, Y. Wang, D. P. Watts, U. Weerasinghe, X. Wei, M. H. Wood, L. Xu, N. Zachariou

Physics Faculty Publications

Extracting accurate results from neutrino oscillation and cross section experiments requires accurate simulation of the neutrino-nucleus interaction. The rescattering of outgoing hadrons (final state interactions) by the rest of the nucleus is an important component of these interactions. We present a new measurement of proton transparency (defined as the fraction of outgoing protons that emerge without significant rescattering) using electron-nucleus scattering data recorded by the CLAS detector at Jefferson Laboratory on helium, carbon, and iron targets. This analysis uses a new data-driven method to extract the transparency. It defines transparency as the ratio of electron-scattering events with a detected proton …

Studying Electroweak Few-Body Observables In Chiral Effective Field Theory, Alex Gnech

Physics Faculty Publications

The use of nuclei to study electroweak probes is becoming increasingly relevant experimentally. The success of dark matter and neutrino experiments strongly depends on the ability to control nuclear effects in order to extract the fundamental parameters associated with external probes. Therefore, reliable theoretical calculations of nuclear structure and reactions, with well-controlled errors, are crucial for the success of experimental efforts. Currently, chiral effective field theory (χEFT) coupled with {\it ab-initio} methods represents one of the best approaches that fulfills these requirements. To use this approach as a tool for studying fundamental physics, it is essential to validate it against …

Dispersion Relations And The Light-Hadron Spectrum, Arkaitz Rodas

Physics Faculty Publications

Light hadron spectroscopy sits in the non-perturbative regime of QCD, where flexible fits often compete with firm principles. Over the past two decades, dispersion relations have become a practical, numerical tool to solve these issues, enabling first-principles analyses and delivering robust resonance parameters. With ππ scattering as an example, we briefly summarize the current landscape, highlight dispersive work that has resolved long-standing debates and set precision standards, and include recent examples of dispersive analyses of lattice QCD results.

Next-To-Next-To-Leading Power Corrections To Unpolarized Semi-Inclusive Deep Inelastic Scattering, Ian Balitsky, Alexei Prokudin

Physics Faculty Publications

Semi-Inclusive Deep Inelastic Scattering (SIDIS) is a key tool for exploring the three-dimensional structure of the nucleon through Transverse Momentum Dependent parton distributions and fragmentation functions. While leading-power contributions to the SIDIS cross-section are well established, next-to-leading power (NLP) corrections of order 1/Q and next-to-next-to-leading power (NNLP) corrections of order 1/Q²  to the hadronic tensor have only recently begun to be systematically investigated. These corrections are essential for reliable phenomenology and interpretation of modern high-precision data. In recent papers by one of the authors, NNLP corrections to the Drell-Yan process were derived using the rapidity factorization formalism. In the present …

Studying Electroweak Few-Body Observables In Chiral Effective Field Theory, Alex Gnech

Physics Faculty Publications

The use of nuclei to study electroweak probes is becoming increasingly relevant experimentally. The success of dark matter and neutrino experiments strongly depends on the ability to control nuclear effects in order to extract the fundamental parameters associated with external probes. Therefore, reliable theoretical calculations of nuclear structure and reactions, with well-controlled errors, are crucial for the success of experimental efforts. Currently, chiral effective field theory (χ EFT) coupled with {\it ab-initio} methods represents one of the best approaches that fulfills these requirements. To use this approach as a tool for studying fundamental physics, it is essential to validate it …

Optical Nonlinearity Of A Cold Atomic Ensemble Driven By A Strong Coherent Field In A Saturation Regime, A. S. Usoltsev, L. V. Gerasimov, A. D. Manukhova, S. P. Kulik, D. V. Kupriyanov

Physics Faculty Publications

We present a microscopic analysis and evaluation of the dielectric susceptibility of a dielectric medium consisting of vector-type two-energy-level atoms, responding to a weak probe mode, when the atoms are driven by a strong coherent field. Each atom, in an environment of others, exists as a quasiparticle, further structuring the bulk medium. In a limit of dilute atomic gas, the dynamics of each atom follows the Mollow-type nonlinear excitation regime, and the medium susceptibility collectivizes the individual atomic responses to the probe mode. We outline how the collective dynamics can be interpolated up to a dense medium, and we argue …

Real-Space Imaging Of The Electron-Pair Density Hole In Molecular Auger-Meitner Decay, Mats Simmermacher, Nathan Goff, Andres Moreno Carrascosa, Elke Fasshauer, Thomas Northey, Lingyu Ma, Haiwang Yong, Brian Stankus, Asami Odate, Xuan Xu, Wenping Du, Kyle Acheson, Joseph C. Cooper, Daniel Ratner, Mengning Liang, Ruaridh Forbes, Michael P. Minitti, Adam Kirrander, Peter M. Weber

Physics Faculty Publications

Electrons in matter can rearrange extremely quickly under external perturbations, underpinning subsequent structural and chemical transformations. Coulomb interactions between neighbouring electrons often shape this response, giving rise to correlated motion and strongly affecting the distribution of electrons in the system. Here we show that non-resonant hard X-ray scattering can directly access changes in the radial electron-pair density during the rapid rearrangement of core and valence electrons. We do this by studying sulfur hexafluoride molecules undergoing Auger–Meitner decay. We exploit a second-order interaction between the X-ray photons and the molecules to trigger and probe the decay dynamics with a single pulse, …

Longitudinal Spin Transfer To Λ Hyperons In Semi-Inclusive Deep Inelastic Scattering With The Clas12 Spectrometer, M. Mceneaney, A. Vossen, A. Acar, P. Achenbach, J. S. Alvarado, M. Amaryan, W. R. Armstrong, H. Atac, N. A. Baltzell, L. Barion, M. Bashkanov, M. Battaglieri, F. Benmokhtar, A. Bianconi, A. S. Biselli, M. Bondi, F. Bossù, S. Boiarinov, K. -Th. Brinkmann, W. J. Briscoe, V. D. Burkert, T. Cao, R. Capobianco, D. S. Carman, J. C. Carvajal, A. Celentano, P. Chatagnon, V. Chesnokov, H. Chinchay, G. Ciullo, P. L. Cole, M. Contalbrigo, A. D'Angelo, N. Dashyan, R. De Vita, M. Defurne, S. Diehl, C. Dilks, C. Djalali, R. Dupre, H. Egiyan, M. Ehrhart, A. El Alaoui, L. El Fassi, M. Farooq, S. Fegan, R. E. Ferguson, I. P. Fernando, A. Filippi, C. Fogler, K. Gates, G. Gavalian, D. I. Glazier, R. W. Gothe, Y. Gotra, B. Gualtieri, K. Hafidi, H. Hakobyan, M. Hattawy, T. B. Hayward, D. Heddle, A. Hobart, M. Holtrop, Y. Ilieva, D. G. Ireland, H. S. Jo, S. Joosten, T. Kageya, A. Kim, V. Klimenko, A. Kripko, V. Kubarovsky, L. Lanza, S. Lee, P. Lenisa, D. Marchand, V. Mascagna, D. Matamoros, B. Mckinnon, T. Mineeva, M. Mirazita, V. Mokeev, C. Munoz Camacho, P. Nadel-Turonski, T. Nagorna, K. Neupane, S. Niccolai, G. Niculescu, M. Osipenko, M. Ouillon, P. Pandey, M. Paolone, L. L. Pappalardo, R. Paremuzyan, E. Pasyuk, S. J. Paul, W. Phelps, N. Pilleux, S. Polcher Rafael, L. Polizzi, J. Poudel, Y. Prok, A. Radic, T. Reed, J. Richards, M. Ripani, P. Rossi, A. A. Rusova, C. Salgado, S. Schadmand, A. Schmidt, M. B. C. Scott, E. V. Shirokov, S. Shresstha, E. Sidoretti, D. Sokhan, N. Sparveris, M. Spreafico, I. Strakovsky, S. Strauch, J. A. Tan, R. Tyson, M. Ungaro, P. S. H. Vaishnavi, S. Vallarino, C. Velasquez, L. Venturelli, H. Voskanyan, E. Voutier, D. P. Watts, Y. Wang, U. Weerasinghe, X. Wei, N. Wickramaarachchi, M. H. Wood, L. Xu, Z. Xu, N. Zachariou, Z. W. Zhao, V. Ziegler, M. Zurek

Physics Faculty Publications

The polarization of Λ hyperons is preserved in the angular distribution of their decay products. This property allows one to study the spin structure of the Λ. In semi-inclusive deep inelastic scattering where a high energy lepton interacts with a nucleon target and one or more hadrons and the scattered lepton are detected in the final state, the probability for a struck quark to impart the polarization of the lepton to the Λ may be measured. In particular, in electron-proton scattering this quantity may be related to the longitudinal light quark polarization of the Λ. Currently, limited experimental data cannot …

Inverse Problem In The Large Momentum Effective Theory Framework, Herve Dutrieux, Joe Karpie, Christopher J. Monahan, Kostas Orginos, Anatoly Radyushkin, David Richards, Savvas Zafeiropoulos

Physics Faculty Publications

One proposal to compute parton distributions from first principles is the large momentum effective theory (LaMET), which requires the Fourier transform of matrix elements computed nonperturbatively. Lattice quantum chromodynamics (QCD) provides calculations of these matrix elements over a finite range of Fourier harmonics that are often noisy or unreliable in the largest computed harmonics. It has been suggested that enforcing an exponential decay of the missing harmonics helps alleviate this issue. Using nonperturbative data, we show that the uncertainty introduced by this inverse problem in a realistic setup remains significant without very restrictive assumptions, and that the importance of the …

Geometry Of Almost-Conserved Quantities In Symplectic Maps: Approximate Invariants In Nonlinear Accelerator Systems, T. Zolkin, S. Nagaitsev, I. Morozov, S. Kladov

Physics Faculty Publications

We present a perturbative method for constructing approximate invariants of motion directly from the equations of discrete-time symplectic systems. This framework offers a natural nonlinear extension of the classic Courant-Snyder (CS) theory for systems with 1 degree of freedom—a foundational cornerstone in accelerator physics now spanning seven decades and historically focused on linear phenomena. The original CS formalism emerged under conditions where nonlinearities were weak, design goals favored linear motion, and analytical tools—such as the Kolmogorov-Arnold-Moser theory—had not yet been fully developed. While various normal-form methods have been proposed to treat near-integrable dynamics, the approach introduced here stands out for …

Exploring Causes Of Beam Loss At Cebaf, C. Matthews, J. Benesch, R. M. Bodenstein, B. Freeman, D. Moser, D. Turner, K. Price, J. Samari, B. Terzić

Physics Faculty Publications

At Jefferson Lab, the Continuous Electron Beam Accelerator (CEBAF) features a unique design with two linear accelerators and two arc sections allowing for multiple turns of the electron beam, as well as four experimental end stations. This topology leads to increased beam losses, especially in the spreader and recombiner regions connecting the arcs to the LINACs and in the extraction regions connecting the experimental end stations to the accelerator. These losses result in equipment activation and operational interruptions. Recent upgrades to the facility’s diagnostic systems, including the addition of xenon ion chambers, have provided higher-resolution data regarding these loss events. …

Interpolation Between Sudakov And Bfkl Rapidity Evolutions For Tmd Factorization At Small X, Ian Balitsky

Physics Faculty Publications

Within the framework of rapidity-only small-x TMD factorization, the evolution with respect to the rapidity cutoff is initially governed by Sudakov double logarithms and subsequently by BFKL/BK single logarithms. The evolution equation proposed in this paper correctly reproduces both the Sudakov and BFKL limits, while providing a consistent interpolation between these two regimes.

Small Language Model Jailbreak Defender Framework, Eduardo Alberto Castro Puello

CCAC Theses and Dissertations

Small Language Models (SLMs) are increasingly deployed in enterprise, edge, and domain‑specialized applications due to their lower computational cost and latency compared to Large Language Models (LLMs). However, SLMs typically exhibit weaker safety alignment and are disproportionately vulnerable to jailbreak, prompt‑injection, and fine‑tuning attacks that can erode refusal behavior and enable unsafe outputs. Existing defensive techniques such as rule‑based filtering or heavy safety fine‑tuning often degrade task performance or introduce excessive over‑refusal, limiting the safe adoption of SLMs in regulated or security‑sensitive environments. This dissertation proposes the design and empirical evaluation of a modular security alignment framework for fine‑tuned SLMs …

Beyond Digital Pessimism: How A Focus On Trust Can Enhance Eu Digital Law, Neil Richards, Woodrow Hartzog, Claire Boine, Lea Despotis

Faculty Scholarship

Lawmakers looking to foster technological innovation on the European market are adopting laws they hope will promote consumer trust in digital products. Their strategy can be broken down into three components. First, they aim to empower consumers to choose how much data they want to share with companies through an express consent framework. Second, they seek to avoid harms from digital products through product safety law such as adapting the Product Safety Regulation to digital products or adopting the AI Act. Third, they endeavor to prevent manipulation of consumers through digital means.

In this essay, we argue that while laudable, …

Taking Scale Seriously In Technology Law, Mark P. Mckenna, Woodrow Hartzog

Faculty Scholarship

Issues of scale—the relationship between the amount of an activity and its associated costs and benefits—permeate discussions around law and technologies. Indeed, it’s not much of an exaggeration to say that scale is the reason for most technology regulation.

But it’s not always clear how lawmakers and judges conceptualize “scale” when approaching questions around automated technologies. Scale is often used intuitively, just to mean “more.” But scale is not always just about more—scale can introduce new harms and benefits along different dimensions, not simply costs or efficiencies of greater magnitude.

In this Article, we argue for a more sustained interrogation …

Spending Programs And The New Roberts Court, Nicole Huberfeld

Faculty Scholarship

The Supreme Court is poised to place new limits on Congress’s spending power at the urging of states vying for regulatory dominance, particularly in health care and public health. This article is the first to highlight and catalog the throughlines of argumentation, which sparked after states successfully challenged the ACA but have grown into opposing more than Medicaid’s cooperative federalism. This means federal and state programs that heavily rely on federal spending power are at risk, so studying this pattern is imperative. The article begins with a descriptive account of increasing spending power challenges, which make use of converging factors …

Informed Applicants: Anti-Discrimination Enforcement Based On The Use Of Criminal Records, Benjamin David Pyle

Faculty Scholarship

Navigating the labor market with a criminal record is treacherous. Countless job applicants will be turned down immediately after a potential employer learns they have had contact with the criminal legal system. Criminal records reflect and exacerbate long-standing racial and economic inequalities in the United States. Thus, the use of records in employment decisions will often implicate anti-discrimination laws. However, successfully enforcing these protections requires job applicants to, at minimum, understand why they were not hired. Many applicants never learn why they were not hired and thus will never be able to protect their rights. This Article argues that understanding …

Against Ai Half Measures, Woodrow Hartzog, Neil Richards, Ryan Durrie, Jordan Francis

Faculty Scholarship

So far, U.S. consumer protection policy for artificial intelligence (AI) accountability has largely consisted of industry-led approaches such as encouraging transparency, mitigating bias, promoting principles of ethics, and empowering people. These approaches are vital, but they are only half measures. To bring AI within the rule of law, lawmakers must start drawing substantive lines.

In this Article, we identify four AI regulatory approaches to consumer, data, and democratic harms as half measures. First, transparency does not produce accountability on its own. Second, while mitigating bias in AI systems is critical, even unbiased systems are a threat to the vulnerable. Third, …

Corporate Childrearing, Katharine B. Silbaugh

Faculty Scholarship

With children influencing a trillion dollars in spending annually, corporations actively seek to shape children's identities in support of consumer culture and profit. Yet there are no scholarly treatments or theories of the legal relationship between children and corporations. Instead, scholars address individual industries such as food, social media, cosmetics, tobacco, or fashion, missing the structural role corporations play in children's identity formation. Family law evaluates child wellbeing interventions using a triangle to map the legal dynamics among child, parent, and state. This article adds corporations as fourth actors, reconceptualizing that triangle as a square. This square provides the first …

Five Lessons From Ken Kersch’S Conservatives And The Constitution For The Present Moment, James E. Fleming, Linda C. Mcclain

Faculty Scholarship

Timothy Snyder’s On Tyranny, a New York Times bestseller, has the subtitle, “Twenty Lessons from the Twentieth Century.” Ken Kersch’s Conservatives and the Constitution: Imagining Constitutional Restoration in the Heyday of American Liberalism (2019) provides at least twenty lessons from the second half of the Twentieth Century about the development of conservative constitutional thought and activism. Although conservatism has changed in many ways since the 1954-1980 period on which Kersch’s book focuses, these lessons are relevant for understanding the present political moment, filled with concerns that the U.S., during the second Trump Administration, is lurching toward tyranny, authoritarianism, and …

The Punishment Paradox, Steven Arrigg Koh

Faculty Scholarship

What does criminal punishment do? Across centuries of criminal legal thought, a shared answer persists: punishment incapacitates the wrongdoer. And yet punishment sometimes yields its opposite. Paradoxically, punishment sometimes becomes a rallying point-expanding community identification and solidarity around the defendant. This Article shows this punishment paradox using the 2023-24 prosecutions of President Trump and recent and historical case examples-from Luigi Mangione to Karen Read to Rosa Parks. By arguing that criminal law can generate solidarity rather than stigma, the Article both rethinks foundational theories of punishment and reconsiders the role of criminal law in democratic politics. Such an approach transcends …

Memory Warriors, Pluralists, And Abnegators In Constitutional Interpretation: An Essay On Jack Balkin's Pluralist Originalism In Memory And Authority, Jed Handelsman Shugerman, Zachary Shugerman Handelsman

Faculty Scholarship

Jack Balkin’s Memory and Authority: The Uses of History in Constitutional Interpretation brings into conversation the scholarly insights of constitutional theory, history, and the growing field of “the politics of memory,” especially the concept of the “memory entrepreneur.”

Balkin appropriately connects the memory wars in American constitutional law back to Eastern

European memory wars during the World Wars and their aftermath. Prompted by Balkin, we turn to Jan Kubik and Michael Bernhard edited volume Twenty Years After Communism (2014), which has become even more widely influential after Putin’s invasion of Ukraine and a new round of Eastern European memory wars. …

Keeping Evidence Real, Anya Bernstein, Julia Simon-Kerr

Faculty Scholarship

Commentators largely agree that the Federal Rules of Evidence have problems. Expert testimony standards admit junk science. Impeachment rules chill defendant testimony. The hearsay regime defies consistent application and obstructs self-representation. The list goes on: Many rules fail to assist, or affirmatively thwart, jurors trying to make good decisions. Such shortcomings disproportionately harm those with the least power in the system, raising profound questions about whether the evidence code serves its statutory mandate—to promote truth and justice in court proceedings. In the face of widely recognized problems, the government body charged with managing the evidence code—the Advisory Committee on Evidence …

Sidelining The Public, Anya Bernstein, Glen Staszewski, Wendy E. Wagner

Faculty Scholarship

This Article challenges the widely held view that Congress is the American government’s institution closest to the people, while administrative agencies are unaccountable and unresponsive. Providing a systematic, side-by-side institutional analysis, we compare the actual practices and capacities of these two institutions to engage affected publics in policymaking. We find that despite the democratic bona fides of an elected legislature, agencies possess superior capacities, more evolved practices, stricter rules, and stronger incentives for meaningful public engagement. Yet these capacities have been eroded—particularly over the last 50 years—by intensifying legal, political, and managerial obstacles. The Supreme Court and political actors have …

Privacy’S Autonomy Thicket: Disentangling Choice, Consent And Control, Jordan Francis, Woodrow Hartzog, Neil Richards

Faculty Scholarship

When it comes to talking about autonomy, privacy law could use a little clarity. Its discourse uses terms like “choice,” “consent,” and “control” to evoke autonomy, but these terms are too rarely defined and too often used interchangeably, even though they can mean very different things. The three terms have become entangled in a way that has become confusing and counterproductive. We call this problem “privacy’s autonomy thicket,” and it matters because it encourages talking past each other in policy debates, enabling the redefinition of these terms in misleading ways that produce weak and disempowering “notice and choice” regimes.

In …

The Anti-Federalism Of Hr1, Nicole Huberfeld

Faculty Scholarship

The budget reconciliation bill signed on July 4, 2025 (“HR1”) weakened the Patient Protection and Affordable Care Act (ACA) and its core goal of near-universal health insurance coverage. To maintain 2017 tax cuts, Congress curtailed the ACA’s Medicaid eligibility expansion; simultaneously, HR1 limited the kinds of options states have been able to exercise within Medicaid while pushing the costs of deep cuts down to states. This essay argues that HR1 embodies an anti-federalism approach, and that anti-federalism is not the same as federalizing health reforms. In the past, Congress sometimes federalized health care or public health reforms to respond to …