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4D

Four-dimensional space, commonly abbreviated as 4D, is a mathematical construct extending three-dimensional Euclidean space by incorporating an additional perpendicular , allowing points to be described by four coordinates rather than three. This fourth spatial , often denoted as w alongside the familiar x, y, and z, enables geometric objects and transformations that transcend human visual intuition, with volumes (or hypervolumes) scaling as the of the linear . In , 4D employs the "hyper-" prefix for analogs of lower-dimensional figures, such as the (or ), a bounded 4D composed of eight cubic cells, sixteen square faces, and thirty-two edges. Key features of 4D space include its role in advanced and , where it exhibits unique properties like the existence of exotic structures not generalizable to arbitrary dimensions, and facilitates projections onto for partial visualization, such as stereographic or cross-sectional methods. Historically developed in the as part of higher-dimensional analysis, 4D concepts underpin modern fields like and , though direct empirical observation remains impossible due to perceptual limits confined to three spatial dimensions. In physics, a distinct but related formulation treats as a four-dimensional continuum, integrating three spatial dimensions with time under Minkowski geometry in Einstein's , fundamentally altering causal structures and predictions for phenomena like . These frameworks highlight 4D's abstract yet indispensable utility in modeling complex systems, from quantum field theories to multidimensional data visualization.

Mathematics and Physics

Four-dimensional space

Four-dimensional extends by adding a fourth orthogonal coordinate , typically denoted as w, resulting in points represented by coordinates (x, y, z, w). The between two points P = (x_1, y_1, z_1, w_1) and Q = (x_2, y_2, z_2, w_2) is given by the [formula d](/page/Formula_D) = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2 + (z_2 - z_1)^2 + (w_2 - w_1)^2}, which generalizes the to four dimensions by summing squared differences along each . This preserves properties such as isotropy and the , allowing constructions analogous to those in lower dimensions, including hyperspheres defined by the equation x^2 + y^2 + z^2 + w^2 = r^2 and hypercubes known as tesseracts. The tesseract, a regular four-dimensional polytope, consists of 8 cubic cells, 24 square faces, 32 edges, and 16 vertices, with its hypervolume (four-dimensional analog of volume) calculated as V = s^4, where s is the edge length; for a unit tesseract (s=1), V=1. First-principles constructions build from lower dimensions: a 0D point extrudes to a 1D line segment, to a 2D square, to a 3D cube, and to the 4D tesseract by further extrusion along the w-axis. These objects underpin n-dimensional generalizations in linear algebra and topology, where four-dimensional manifolds serve as models for smooth, locally Euclidean spaces without boundary. Historical development traces to the mid-19th century, with Bernhard Riemann's 1854 habilitation lecture formalizing n-dimensional Riemannian manifolds through metric tensors describing infinitesimal distances, laying groundwork for higher-dimensional geometry independent of embedding in Euclidean space. Earlier intuitions appeared in works like Edwin A. Abbott's Flatland (1884), which employed the analogy of two-dimensional beings encountering three-dimensional intrusions—such as a sphere appearing as a growing and shrinking circle—to convey perceptual challenges of higher dimensions. Human perception, constrained by three-dimensional sensory input, precludes direct visualization of , necessitating indirect methods like orthogonal onto three or two dimensions or analogies such as cross-sections (slicing a 4D object to reveal 3D volumes) and net unfoldings (analogous to nets). Schlegel diagrams provide a perspective of a 4D polytope's into three dimensions, with one at the center and others surrounding it, further projectable to two dimensions for rendering. In , four-dimensional spaces reveal phenomena, such as the possibility of exotic smooth structures on \mathbb{R}^4, differing from lower dimensions. Applications include modeling quasicrystals in , where certain quasiperiodic structures emerge as projections of periodic lattices from , influencing mechanical and topological properties observable in three dimensions. In computational simulations of , configuration spaces are embedded in high-dimensional Euclidean spaces (including four-dimensional approximations) to capture the vast in polypeptide chains, facilitating analysis of folding landscapes and energy minima via techniques.

Spacetime in special and general relativity

In special relativity, spacetime constitutes a four-dimensional continuum merging three spatial dimensions with time, formalized as to preserve the invariance of the c across inertial frames. presented this geometric interpretation in 1908, building on Einstein's 1905 postulates that reject an absolute luminiferous ether and enforce Lorentz transformations. The line element ds^2 = -c^2 dt^2 + dx^2 + dy^2 + dz^2 defines the proper interval between events, invariant under Lorentz boosts, with the negative for the time component yielding a (indefinite) signature that distinguishes timelike paths (possible for massive particles) from spacelike separations (acausal). emerge from null intervals (ds^2 = 0), bounding causal domains: events within the future can influence an observer, while those outside cannot, grounding in the metric's rather than Euclidean equivalence of dimensions. This framework derives from empirical null results like the 1887 Michelson-Morley experiment, which measured no directional variation in light speed, contradicting ether drag predictions and supporting light's frame-independence. and follow directly, validated in particle accelerators where lifetimes extend by factors matching \gamma = 1/\sqrt{1 - v^2/c^2}. In applications, (GPS) satellites require daily corrections of approximately 38 microseconds for net clock gain from special relativistic velocity effects (slowing) and weaker (speeding), ensuring positional accuracy within meters; uncorrected, errors would accumulate to kilometers daily. General relativity extends Minkowski spacetime to a pseudo-Riemannian manifold curved by mass-energy, as Einstein finalized in November 1915 via field equations G_{\mu\nu} = (8\pi G/c^4) T_{\mu\nu}, where geometry encodes gravitational causation. Mercury's perihelion advances 43 arcseconds per century beyond Newtonian mechanics, precisely matching observed residuals after planetary perturbations, a prediction unexplained by alternatives like until GR's tensorial curvature. Direct tests include the 2015 detection of from merger GW150914, with strain h \approx 10^{-21} rippling flat spacetime approximations, confirming quadrupole radiation formulas over scalar or vector gravity theories lacking empirical support. Misinterpretations equating time fully to space ignore the metric's signature, which precludes closed timelike curves in asymptotically flat regions and upholds against acausal artifacts in analogies.

Extra dimensions and theoretical models

Kaluza-Klein theory, proposed by in 1919 and refined by in 1926, extends to five dimensions, interpreting as geometric effects arising from the compactified into a small circle of radius on the order of the Planck length. This framework aimed to unify and without introducing new fields, deriving from the five-dimensional Einstein equations under the cylinder condition that fields are independent of the extra coordinate. Despite its elegance, the theory lacks direct experimental verification, as no observable deviations from four-dimensional physics have confirmed the extra dimension, and quantum inconsistencies persist without modern extensions. Contemporary theoretical models build on this idea, positing multiple compactified to reconcile and . String theory, formalized in the 1980s, requires 10 dimensions—nine spatial and one temporal—with six spatial dimensions curled up via structures like Calabi-Yau manifolds to evade detection at macroscopic scales. , introduced in 1995 by , encompasses string theories within an 11-dimensional framework, where the extra dimension emerges dynamically through dualities and configurations. These models promise unification of all fundamental forces, with enabling vibrational modes of strings to correspond to particles and interactions. However, extra-dimensional theories face substantial empirical challenges. experiments through 2025 have yielded null results for supersymmetric particles, a cornerstone prediction in many string-inspired models, excluding gluinos and squarks up to masses exceeding 2 TeV and first-generation sleptons to nearly 400 GeV. The theory's vast landscape of approximately $10^{500} possible vacua, arising from different compactification geometries and fluxes, undermines by allowing virtually any low-energy observation to fit some configuration, rendering the framework difficult to falsify. Absent confirmatory evidence, such as microscopic production or deviations in gravitational force laws at sub-millimeter scales, these hypotheses prioritize mathematical consistency over causal mechanisms grounded in observable four-dimensional . Laboratory simulations of higher dimensions provide analogs but no fundamental validation. In 2023, researchers at the developed metamaterials exploiting synthetic dimensions—internal like or —to manipulate energy waves in an effective , enabling precise control of wave paths unattainable in . These engineered systems, which map physical parameters to higher-dimensional lattices, demonstrate wave phenomena mimicking extra-dimensional but rely on artificial constructs rather than intrinsic structure, highlighting technological utility over evidence for unseen spatial extents. Such approaches underscore the distinction between simulated higher-dimensional effects and verifiable extensions of physical reality.

Technology and Computing

4D printing and adaptive materials

refers to the additive manufacturing of three-dimensional structures embedded with stimuli-responsive materials that undergo programmed transformations over time in response to external triggers such as temperature, moisture, light, or magnetic fields. The term was coined by Skylar Tibbits of Self-Assembly Lab in 2013, building on by incorporating a —time—to enable dynamic reconfiguration of printed objects. These materials, often shape-memory polymers or composites, exploit differential expansion or contraction; for instance, hydrophilic hydrogels swell upon to actuate self-assembling hinges or biomedical implants like expandable stents. Early prototypes demonstrated water-responsive mechanisms, with hydrogels expanding over 200% in volume due to moisture absorption, as explored in foundational research on . More recent advancements include Khalifa University's 2024 vat photopolymerization of photochromic Fresnel lenses that dynamically alter focal properties and block UV light under exposure. In 2025, magnetically responsive composites have advanced applications, enabling shape changes via external fields for precise actuation in biomedical and robotic systems, as reviewed in NIH-funded studies. The technology has shown empirical shape recovery rates exceeding 91% in controlled tests, with some composites achieving 100% fixity and recovery in initial cycles under thermal stimuli. Applications span , where 4D-printed composites enable morphing wings that adapt to flight conditions for improved efficiency, as demonstrated in Concordia University's wing prototypes and NASA-MIT collaborations on shape-shifting structures. In pharmaceuticals, 4D printing facilitates personalized systems that release payloads in response to physiological cues like or , enhancing compliance. Market projections reflect growing interest, with the global sector valued at US$213.76 million in 2024 and forecasted to reach US$3,313.32 million by 2033 at a CAGR of approximately 35%. Despite these advances, faces scalability hurdles, including slow actuation times—such as hours required for drying—and high material costs that limit production volumes compared to conventional . Empirical durability tests reveal reduced mechanical strength and resistance in adaptive structures versus static prints, with shape-memory alloys prone to degradation over repeated cycles. These limitations have tempered early hype, as real-world pilots, such as explorations by HDI Global in 2025, highlight the need for cost reductions and faster responses to achieve broader viability.

4D visualization and computational modeling

Visualization of four-dimensional (4D) objects requires projecting higher-dimensional onto lower-dimensional spaces accessible to human and current , typically through or representations. Common techniques include orthographic and projections from 4D to , followed by further to screens, which preserve structural analogies like wireframes or slices. Ray tracing methods extended to 4D treat the fourth dimension as an additional for calculations, enabling rendering of solid volumes by simulating light paths in , as demonstrated in early implementations for 4D fractals and objects. Topology-based approaches leverage manifold properties to interpret 4D structures without full geometric rendering, focusing on invariant features like connectivity and to "slice" or embed 4D spaces into comprehensible forms, such as through cross-sections or unfolding analogies. Software tools support these methods indirectly; for instance, Mathematica facilitates 4D coordinate plotting in xyzw systems for projections, while custom extensions to ray tracers like POV-Ray handle exported scenes for enhanced lighting and depth cues. Empirical validations, such as University's 2017 explorations of 4D plotting, confirm that coordinate-based projections accurately depict distortions under rotation, aligning with mathematical expectations despite perceptual limitations. In applications, computational modeling simulates 4D dynamics for physics and graphics, including animations of rotations where dual cubes morph via 4D transformations, rendered through iterative projection matrices to mimic motion. Integration with (VR) and (AR) provides pseudo-4D immersion by mapping 4D slices to stereoscopic views, as in interactive hypersphere applications that allow users to navigate manifold embeddings for educational insights. Recent developments incorporate for reconstruction, aiding rendering of complex 4D data by optimizing neural approximations of multidimensional manifolds, particularly useful for reducing high-dimensional datasets to analyzable 4D forms in scientific . Despite advances, 4D rendering faces severe hardware constraints, with scaling poorly—often approaching O(n^4) for volume intersections in grid-based methods due to the in elements—necessitating approximations like sparse sampling or hierarchical bounding volumes to achieve feasible runtimes. These techniques yield projections that convey topological but do not enable direct perceptual access to 4D , as human remains anchored in three spatial dimensions, underscoring the reliance on mathematical rigor over intuitive .

4D as a database system

4D is a management system (RDBMS) integrated with an application development environment, enabling the creation of custom through a combination of data storage, querying, and graphical interface design tools. Developed by Laurent Ribardière in 1984 as "4th Dimension," it originated from early efforts to provide a graphical for professional application building on platforms like the Macintosh. The system evolved under ACI US (later 4D Inc.), incorporating support for SQL standards alongside a 4D language that allows developers to define data models, , and user interfaces within a unified . Central to 4D's design is its built-in form and menu designer for constructing graphical user interfaces without external tools, alongside client-server architecture that supports multi-user deployments for distributed applications. The Object Relational Data Access (ORDA) feature, enhanced in versions like v19 released around 2021, provides an object-oriented layer over relational data for more efficient querying and manipulation, reducing boilerplate code in application development. These elements make 4D suitable for building standalone or web-connected apps handling structured data, such as inventory tracking or CRM systems, where integrated development accelerates deployment compared to assembling separate database and frontend components. With over 40 years of continuous refinement since its inception, 4D demonstrates empirical stability in maintaining and core functionality across operating systems, appealing to small and medium-sized enterprises (SMEs) that prioritize reliable, low-maintenance solutions over cutting-edge . Its rapid prototyping capabilities—stemming from the all-in-one environment—offer practical advantages for iterative business app development, where developers can prototype, test, and refine without switching between disparate tools, contrasting with pure SQL systems that demand additional frameworks for and logic integration. Market adoption persists in niche sectors requiring customized, on-premise or hybrid deployments, underscoring its utility for non-enterprise-scale operations. To address limitations in handling very large datasets, where independent evaluations highlight slower query performance relative to optimized open-source RDBMS like in high-volume scenarios, recent updates emphasize cloud-compatible integrations and hybrid architectures for improved scalability. These adaptations, including support for and hosting options, enable 4D applications to leverage external services for data-intensive tasks while retaining core strengths in application logic.

Arts and Entertainment

Fourth dimension in visual arts

The concept of the fourth dimension entered visual arts in the early 20th century as artists sought to depict multiple perspectives and non-Euclidean spatial relationships, drawing from mathematical ideas of hyperspace rather than temporal or mystical interpretations. Maurice Princet, a mathematician frequenting Pablo Picasso's circle in Paris around 1903, introduced concepts from Henri Poincaré's work and Esprit Jouffret's 1903 book Traité élémentaire de géométrie à quatre dimensions, influencing Cubist experiments in simultaneous viewpoints. This period, spanning Picasso's proto-Cubist works from 1907 to analytic Cubism by 1914, used fragmented forms to evoke multidimensional perception, as seen in Picasso's Les Demoiselles d'Avignon (1907), where angular distortions simulate rotations in higher dimensions. Critics have debated the depth of this mathematical influence, with some art historians labeling claims of direct fourth-dimensional inspiration on a "" propagated by later interpretations, arguing that Picasso denied overt reliance on such and that stylistic shifts stemmed more from perceptual than precise hyperspace modeling. Nonetheless, these efforts expanded viewer by challenging representation, prioritizing empirical analogies to and slicing techniques over or pseudoscientific notions of ethereal realms, which lacked verifiable geometric basis. In mid-20th-century , explicitly incorporated fourth-dimensional forms, as in his 1954 oil painting Crucifixion (Corpus Hypercubus), featuring an unfolded () as the cross to symbolize divine hyperspatial transcendence while grounding it in mathematical unfolding. Dalí collaborated with mathematicians like Thomas Banchoff to visualize such projections, using stereo effects for perceptual depth beyond three dimensions. Later artists like Tony Robbin advanced these ideas through sculptures and paintings of tessellations, beginning in the late after consulting with Banchoff on 4D rotations and distortions. Robbin's works, such as projections in his 1992 book fourfield: Computers, Art & the 4th Dimension, employ wireframes and color to render 4D polytopes in 3D space, fostering interactive viewer engagement with non-intuitive geometries. Contemporary math-art intersections, documented in proceedings like the 2016 Bridges Conference, continue this tradition via computational projections that analogize hyperspace slicing for perceptual experiments. These approaches achieve cognitive expansion by verifiable projection methods, distinguishing empirical art from unsubstantiated mystical claims.

4D cinema and immersive experiences

4D cinema refers to motion picture presentations that combine three-dimensional visuals with synchronized sensory effects, such as seat vibrations, wind bursts, water sprays, scents, and strobe lighting, to simulate physical immersion in the film's action. This format evolved from early prototypes like Morton Heilig's Sensorama, a multi-sensory simulator developed starting in 1957 and prototyped by 1962, which integrated stereoscopic 3D imagery, motion simulation, audio, wind, and odors to evoke environmental realism in a booth accommodating up to three viewers. Unlike static cinema, 4D effects are algorithmically timed to on-screen events, often using pneumatic or hydraulic actuators in theater seats to replicate movements like tilts, jolts, or rotations. Modern 4D systems, exemplified by CJ 4DPLEX's technology introduced in 2009, employ proprietary algorithms that parse data to generate per-seat effects via networked actuators, enabling effects like leg ticklers or back pokers for precise haptic feedback. The first 4DX theater opened in , , in 2009, with effects calibrated to avoid overpowering the narrative while enhancing causal links between visual cues and physical sensations, such as wind during flight scenes or scents for environmental context. Patents like US7934773B2 detail synchronized motion induction in seats relative to video playback, using transducers to translate digital signals into multi-axis movements without requiring full simulator gimbals. Technical challenges include synchronizing effects across rows via "master-slave" drive mechanisms, as patented by MediaMation in 2013, to minimize latency and ensure uniform audience response. Key milestones include the 2010 release of in 4DX format in and , where augmented effects like explosive scents and seat shakes drew premium ticket sales at $15.80 versus standard $6.90, marking an early commercial success for sensory . Adoption expanded globally, with the first U.S. 4DX venue at Regal in 2014, European rollout via in 2017, and partnerships like in since 2011 leading to over 50 theaters by 2025. In the 2020s, 4D integrations grew in theme parks, such as SimEx-Iwerks' ultra-accessible 4D platforms at in 2025, featuring wheelchair-compatible motion bases for inclusive sensory rides. Audience reception data indicates heightened sensory engagement, with effects fostering multisensory causality that aligns physical responses to events, though empirical studies reveal trade-offs. A experimental analysis found correlations between 4D motion intensity and viewer discomfort, including elevated scores linked to vestibular mismatches, particularly in susceptible individuals. Related research on 3D-augmented formats shows symptoms like oculomotor strain and disorientation increasing by up to 20-30% in motion-heavy sequences, with women reporting higher incidence due to visual-vestibular sensitivities. Proponents argue these elements boost immersion by 20-30% in subjective engagement metrics from pilot studies, yet critics note potential distractions, as effects can prioritize over coherence. High implementation costs—seats exceeding $10,000 each plus effect licensing—limit to premium multiplexes, confining 4D to about 700 global screens as of 2025. Despite hype, disinterested evaluations emphasize verifiable patents over unproven psychological benefits, with risks underscoring the need for viewer warnings and adjustable intensity controls.

4D in literature, music, and philosophy

In literature, ' The Time Machine (1895) popularized the concept of time as a fourth dimension traversable like spatial ones, with the Time Traveller asserting that "there are really four dimensions, three which we call the three planes of Space, and a fourth, Time." This narrative blends spatial navigation with temporal progression, portraying the fourth dimension as a medium for human agency amid evolutionary decline. Earlier, Edwin A. Abbott's : A Romance of Many Dimensions (1884) used a two-dimensional world to analogize higher dimensions, inspiring extensions in fiction where three-dimensional beings encounter four-dimensional intrusions, challenging perceptual limits without direct temporal fusion. Modern , such as Rudy Rucker's Spaceland (2002), critiques dimensionality constraints by depicting protagonists navigating four-spatial-dimensional realms, highlighting ontological puzzles like non-Euclidean geometries and identity fragmentation across extents. References to four-dimensional concepts in music remain scarce and largely symbolic, often evoking hyperspatial abstraction through structural innovation rather than literal representation. For instance, ' album The Fourth Dimension in Sound (1961) employs arrangements with spatial layering to suggest multidimensional depth, though its inspiration draws more from perceptual expansion than mathematical . Experimental works like Keith Lay's Four Dimensions (2012) integrate orchestral elements with electronic synthesis to simulate temporal-spatial interplay, using an electronic wind instrument to bridge auditory "dimensions" in a seven-minute composition. Such efforts prioritize evoking perceptual transcendence over rigorous geometric mapping, reflecting the challenge of translating four-dimensional into sequential sound. In philosophy, , also termed , posits that objects persist as extended "worms" through , comprising temporal parts analogous to spatial ones, thereby resolving puzzles of change via part-whole relations. Theodore Sider formalized this in Four-Dimensionalism: An Ontology of Persistence and Time (2001), arguing that everyday persistence language accommodates temporal parts, such as a person's infancy stage as a proper part of their full four-dimensional self, supported by linguistic evidence like "is shaped like a " applying to wholes over times. This view contrasts with presentism, which denies and future existence, leading to debates over empirical persistence: aligns with causal continuity in but faces critiques for diluting , as the "you" now is merely a temporal slice, not the enduring whole, potentially undermining intuitive self-unity. Proponents credit it with advancing causal by modeling events as intersections, yet detractors highlight unfalsifiable metaphysics, lacking direct empirical disconfirmation beyond theoretical coherence with physics. These ontological tensions persist, with offering explanatory power for diachronic relations at the cost of presentist intuitions about temporal immediacy.

Commercial and Miscellaneous Uses

In , 4D Building Information Modeling (BIM) integrates time as a into models to simulate construction sequences, enabling project teams to visualize progress, detect scheduling conflicts, and optimize . This approach has been applied commercially since the early , with firms using it to reduce delays by up to 20% through early identification of logistical issues, such as equipment clashes or labor overlaps. For instance, in and building projects, 4D BIM facilitates safer site operations by forecasting high-risk phases and supports cost savings via precise material delivery timing. Precision employs 4D for non-contact surface measurements in , where the accounts for dynamic environmental factors like to ensure accurate defect detection on and components. 4D Technology Corporation, founded in 2001, commercializes products such as the AccuFiz interferometer and the handheld 4D , which measure surface flaws down to micrometer scales in industries including , automotive, and semiconductors. These tools are deployed in production environments, enabling for applications like mirrors and engine parts, with the model specifically designed for shop-floor portability since its 2017 release. Miscellaneous applications include geophysical modeling, where 4D geometric computations analyze volumetric curvatures of subsurface features for oil exploration and seismic , aiding commercial resource extraction decisions. In parameter optimization for engineering design, such as cell phone tuning, 4D spaces represent multi-variable trade-offs to minimize trial-and-error in product development. These uses leverage abstract 4D for practical efficiency gains without physical instantiation of higher-dimensional objects.

References

  1. [1]
    Four-Dimensional Geometry -- from Wolfram MathWorld
    Four-dimensional geometry is Euclidean geometry extended into one additional dimension. The prefix "hyper-" is usually used to refer to the four- (and higher-) ...
  2. [2]
    What is a four dimensional space like? - University of Pittsburgh
    A four-dimensional space, like a tesseract, is hard to visualize, but is like a cube with one extra dimension. It has 8 faces, and its volume is L^4.
  3. [3]
    4D Geometry - TensegrityWiki
    Apr 11, 2022 · Four dimensional (4D) geometry was a theme of art, science and philosophy in the late 19th century. It influenced leading scientists and artists ...
  4. [4]
    Can our brains see the fourth dimension? - Science | HowStuffWorks
    Sep 20, 2023 · Four-Dimensional Space (4D): In physics, time is often considered the fourth dimension, essential in understanding space-time in Einstein's ...
  5. [5]
    Unlocking the Secrets of a 4D Cosmos - USC Dornsife
    Feb 1, 2023 · Math collaborators work toward advances in four dimensions. Mathematicians trying to describe spacetime do so by specifying four dimensions: ...
  6. [6]
    Is the Distance Formula applicable for 4-Dimensional Coordinate ...
    Oct 18, 2019 · It means the same thing in four dimensions as in two or three. It is the distance between two points, the length of the line segment connecting them.Euclidean distance formula in higher dimensionsEuclidean distance between 4-dimensional vectors [closed]More results from math.stackexchange.com
  7. [7]
    Tesseract - Geometry Calculator - Rechneronline
    Calculations at a tesseract. This is a four-dimensional hypercube, the expansion of square (2D) and cube (3D) into a fourth dimension of space.
  8. [8]
    1854: Riemann's classic lecture on curved space
    Jun 1, 2013 · Riemann extended that notion to spaces with any number of dimensions, demonstrating that one needs six numbers to describe the curvature of any ...
  9. [9]
    Aspiring to a Higher Plane - The Public Domain Review
    Sep 19, 2011 · In 1884 Edwin Abbott Abbott published Flatland: A Romance of Many Dimensions ... analogy, widely used ever since, and not entirely Abbott's ...Missing: dimensionality | Show results with:dimensionality
  10. [10]
    [PDF] 4D Exploring System for Intuitive Understanding of 4D Space
    At the end of the 19th century, Victor Schlegel initially attempted to visualize 4D objects using Schlegel diagrams [Sch83]. Shortly thereafter, in the ...
  11. [11]
    Greetings from the fourth dimension: Scientists glimpse 4D crystal ...
    Feb 13, 2025 · Using this realization, the physicists were able to describe and predict mechanical and thermodynamic properties of quasicrystals. The concept ...
  12. [12]
    Protein Folding in High-Dimensional Spaces - PubMed Central - NIH
    We explore the consequences of very high dimensionality in the dynamical landscape of protein folding. Consideration of both typical range of stabilizing ...Figure 1 · Relaxation Functions In... · Figure 4
  13. [13]
    [PDF] Hermann Minkowski and the scandal of spacetime - HAL-SHS
    Sep 6, 2008 · When Hermann Minkowski's first paper on relativity theory [8] appeared in. April 1908, it was met with an immediate, largely critical ...
  14. [14]
    November 1887: Michelson and Morley report their failure to detect ...
    Nov 1, 2007 · ... Michelson and Morley couldn't detect evidence of motion through the ether. They reported their null result in November 1887 in the American ...
  15. [15]
    Real-World Relativity: The GPS Navigation System
    Mar 11, 2017 · A calculation using General Relativity predicts that the clocks in each GPS satellite should get ahead of ground-based clocks by 45 microseconds per day.
  16. [16]
    100 Years of General Relativity | NASA Blueshift
    Nov 25, 2015 · General relativity is a way to describe gravity by attributing it to the curvature of space-time that occurs in the presence of massive bodies.
  17. [17]
    Precession of the perihelion of Mercury
    As seen from Earth the precession of Mercury's orbit is measured to be 5600 seconds of arc per century (one second of arc=1/3600 degrees). Newton's equations, ...
  18. [18]
    Gravitational Waves Detected 100 Years After Einstein's Prediction
    Feb 11, 2016 · The gravitational waves were detected on September 14, 2015 at 5:51 a.m. Eastern Daylight Time (09:51 UTC) by both of the twin Laser ...
  19. [19]
    [PDF] Kaluza-Klein Gravity - arXiv
    Kaluza unified not only gravity and electromagnetism, but also matter and geometry, for the photon appeared in four dimensions as a manifestation of empty five ...
  20. [20]
    [PDF] A Brief Summary of Kaluza-Klein Theory - The Physics Mill
    May 3, 2013 · First, we describe Kaluza's original “cylinder condition” and how this allows for the unification of Einstein gravity and electromagnetism in a ...
  21. [21]
    Kaluza, Klein and their story of a fifth dimension | plus.maths.org
    Oct 10, 2012 · Although Kaluza and Klein's theory seemed to unify the forces of electromagnetism and gravity it wasn't widely accepted when it was published in ...
  22. [22]
    Why are there specifically 10, 11, or 26 dimensions in string theory?
    Nov 15, 2016 · Current string theories state that there are 10, 11, or 26 spacetime dimensions in superstring theory, M-theory, and bosonic string theory, respectively.<|control11|><|separator|>
  23. [23]
    The Origins of the Universe: M-theory
    This seems to be telling us that M-theory should be viewed as an 11 dimensional theory that looks 10 dimensional at some points in its space of parameters. ...
  24. [24]
    [PDF] Who's Counting? Is it 10 or 11? (dimensions, that is
    If the total number of dimensions is not 10 or 11, then necessarily some of the dimensions have string size and are therefore harder to describe. What is the ...
  25. [25]
    Supersymmetry Washes Out at the Large Hadron Collider
    Mar 25, 2025 · Calculations to predict the masses of superpartners were prone to upward revision after each null result across multiple generations of ...<|separator|>
  26. [26]
    The landscape and the multiverse: What's the problem? | Synthese
    Apr 18, 2021 · We argue first that the landscape problem relies on dubious assumptions and does not motivate a multiverse hypothesis. Nevertheless, we then ...
  27. [27]
    Will We Ever Prove String Theory? - Quanta Magazine
    May 29, 2025 · Yet despite its mathematical elegance, the theory still lacks empirical evidence. One of its most intriguing, yet vexing, implications is that ...
  28. [28]
    Mizzou Engineers create novel approach to control energy waves in ...
    Jul 30, 2023 · “But now we are building materials in the synthetic dimension, or 4D, which allows us to manipulate the energy wave path to go exactly where we ...
  29. [29]
    Innovative Method for 4D Energy Wave Control - AZoM
    Aug 1, 2023 · But now we are building materials in the synthetic dimension, or 4D, which allows us to manipulate the energy wave path to go exactly where we ...
  30. [30]
    MIT Unveils 4D Printing - Engineering.com
    Feb 28, 2013 · Skylar, who is also a TED2012 Senior Fellow, recently presented a new concept at TED2013: 4D printing – where materials can be reprogrammed to ...Missing: origin | Show results with:origin
  31. [31]
    MIT's Crazy Materials Could Make for Self-Assembling Ikea Furniture
    Nov 10, 2014 · Tibbits refers to these processes collectively as "4-D printing." It's like 3-D printing but with a fourth dimension: time, or as Tibbits likes ...
  32. [32]
    Revolutionizing manufacturing: A review of 4D printing materials ...
    Hydrogels are gaining popularity as active materials in 4D printing due to their ability to drastically alter their volume in response to stimuli, making them ...
  33. [33]
    4D Printing: A Review on Recent Progresses - PMC - NIH
    4D printing was originally defined with the formula of “4D printing = 3D printing + time”, which refers to changes in the shape, structure, or function of 3D ...
  34. [34]
    Development of 4D printed smart fresnel lenses
    Researchers at Khalifa University have developed switchable 4D printed Fresnel lenses with dynamic photochromic and UV-blocking properties using vat ...
  35. [35]
    4D Printing of Magnetically Responsive Materials and Their ... - NIH
    Sep 22, 2025 · Magnetically responsive materials are stimulated by magnetic fields to change their shapes, properties, or functions.Missing: NASA | Show results with:NASA<|separator|>
  36. [36]
    Controlling Morphing Behavior in 4D Printing: A Review About ...
    All printed specimens exhibited a shape recovery rate of >91%. However, in this work, it was found that the shape recovery rates of the lowest samples occurred ...
  37. [37]
  38. [38]
    4D composite printing can improve the wings of drones, according to ...
    May 10, 2022 · 4D composite printing can improve the wings of drones, according to new Concordia research. Suong Hoa's manufacturing technique could make small aircraft ...
  39. [39]
    Understanding the Promise of Smart Materials and 4D Printing
    In aerospace, MIT and NASA have already developed a shape-shifting wing that adjusts mid-flight to reduce fuel burn, emissions, and maintenance costs. In health ...
  40. [40]
    Revolutionizing Personalized Medicine with 4D Printing in Drug ...
    Apr 18, 2025 · Different from conventional technologies, 4D printed systems can control the administration rate of drugs depending on the internal environment ...
  41. [41]
    Global 4D Printing Market to Worth Over US ... - GlobeNewswire
    Jun 13, 2025 · Chicago, June 13, 2025 (GLOBE NEWSWIRE) -- The global 4D printing market was valued at US$ 213.76 million in 2024 and is expected to reach ...
  42. [42]
    New Trends in 4D Printing: A Critical Review - MDPI
    In liquid-responsive materials, the transformation is designed to induce different swelling in distinct compartments, which is dependent upon spatial and ...
  43. [43]
    4D Printing: The Development of Responsive Materials Using 3D ...
    Humidity-responsive materials can swell up or shrink in the presence or absence of liquid, which makes them attractive for 4D printing [176].Missing: NASA | Show results with:NASA
  44. [44]
    How 4D printing is redefining manufacturing - HDI Global
    How 4D printing is redefining manufacturing. 28 May 2025. Exploring self-transforming materials and their game-changing impact on design, production, and ...Missing: pilots | Show results with:pilots
  45. [45]
    4D printing: Fundamentals, materials, applications and challenges
    Jul 16, 2021 · 4D printing refers to single-material or multi-material printing of a device or object that can be transformed from a 1D strand into pre-programed 3D shape.
  46. [46]
    Four-Space Visualization of 4D Objects - Steve Hollasch on GitHub
    This research covers the visualization of four dimensional objects through wireframe methods with extended visualization cues, and through raytracing methods.
  47. [47]
  48. [48]
    Raytracing 4D fractals, visualizing the four dimensional properties of ...
    Nov 20, 2008 · In this paper we describe our attempt to extend the already established technique of ray tracing Julia sets to fully incorporate its four dimensional ...<|separator|>
  49. [49]
    How to 'See' the 4th Dimension with Topology - Quanta Magazine
    the study of shapes, or manifolds, that resemble flat Euclidean spaceMissing: based | Show results with:based
  50. [50]
    Visualizing the Fourth Dimension - Duke Research Blog
    Apr 26, 2017 · Plotting four dimensions in the xyzw coordinate system. One commonly explored 4D object we can attempt to visualize is known as a hypercube.
  51. [51]
    4-D (sphere space) Ray Tracing Algorithm - UMD Computer Science
    The goal of the new algorithm is to minimize the rendering time by improving the average time of the ray-object intersection tests. The algorithm focuses on ...
  52. [52]
    Digital Culture & AudioVisual Challenges | 4D hypersphere Perception
    The user experiences a pseudo-augmented environment which may be useful to comprehend the hypersphere properties. Both these applications are described in the ...
  53. [53]
    AI-Powered Approaches for Hypersurface Reconstruction in ... - MDPI
    The present article explores the possibilities of using artificial neural networks to solve problems related to reconstructing complex geometric surfaces.
  54. [54]
    Unity 4D #3: Rendering 4D Objects - Alan Zucconi
    Jul 6, 2023 · This article will explain how to render 4D objects in Unity, using three separate technique: orthographic projection, perspective projection and cross-section.
  55. [55]
    About us - 4D
    Laurent Ribardière created 4D in 1984 with one goal: to simplify the creation of professional applications by using a fully graphical relational database.Missing: history ACI
  56. [56]
    4D: Fast development platform for business apps
    4D provides integrated platforms that simplify and speed up the development and deployment of Web, mobile, desktop, and client-server applications.
  57. [57]
    What's new in 4D v19 - 4D Blog
    4D v19 continues to bring enhancements to ORDA. Besides the diverse features available (see below), ORDA makes it possible to create high-level class functions ...Missing: GUI | Show results with:GUI
  58. [58]
    4D v19: Evolution of Client/Server Application Building
    Jun 2, 2021 · You will find your client and server applications inside the [name of your base]_build folder located in the same folder as your database.Missing: designer | Show results with:designer
  59. [59]
    4D
    Dec 10, 2019 · The project lead, Laurent Ribardière, left Apple and continued to develop the DBMS, ultimately releasing it under the name 4th Dimension.Missing: ACI | Show results with:ACI
  60. [60]
    [PDF] The Fourth Dimension in Mathematics and Art - The Bridges Archive
    Jul 1, 2016 · This paper gives a brief overview of the background that leads to the study of the fourth dimension and focuses on the specifics of mathematics ...
  61. [61]
    Painting by numbers - Engelsberg ideas
    Dec 23, 2020 · In 1903, Princet showed his friend, Picasso, the works of Henri Poincare and explained the concept of the fourth dimension to the budding genius ...
  62. [62]
    Pablo Picasso - Linda Hall Library
    Apr 8, 2025 · But Henderson went further, discovering that Picasso had been introduced to Jouffret's book by a mathematician in his entourage, Maurice Princet ...
  63. [63]
    Henri Poincaré: the unlikely link between Einstein and Picasso
    Jul 17, 2012 · Picasso was particularly struck by Poincaré's advice on how to view the fourth dimension, which artists considered another spatial dimension.
  64. [64]
    Cubism and the Fourth Dimension: a Myth in Modern Criticism
    Jul 1, 2024 · Cubism not only changed the face of art for all the coming generation, it did so with a suddeness unprecedented in the history of artistic ...Missing: pseudoscience | Show results with:pseudoscience
  65. [65]
    Cubism and the Fourth Dimension: a Myth in Modern Criticism
    Cubism and the Fourth Dimension: a Myth in Modern Criticism. John Adkins ... and "Cubism and Science," The Journal of Aesthetics and Art Criticism, Vol.Missing: pseudoscience | Show results with:pseudoscience
  66. [66]
    A New Facet of Cubism: 'The Fourth Dimension' and 'Non-Euclidean ...
    Princet's mathematical training and his probable familiarity with the geometry of four dimensions have already been mentioned. Although Picasso has denied that ...
  67. [67]
    The painter who entered the fourth dimension - BBC
    May 11, 2016 · A 1954 painting by Salvador Dalí features a mysterious, four-dimensional 'hypercube'. Fiona Macdonald finds out how maths fascinated the ...
  68. [68]
    [PDF] Salvador Dalí and the Fourth Dimension - The Bridges Archive
    Salvador Dalí often used mathematical objects and ideas in his paintings and he enjoyed sharing ideas with mathematicians and scientists.
  69. [69]
    Tony Robbin Hypercubes - Brown Math
    These ideas, for which he is best known as an artist and author, transformed from interstes to plans when Robbin met with Thomas Banchoff in 1979. Banchoff ...
  70. [70]
    The First Virtual Reality | The Saturday Evening Post
    Jul 18, 2019 · Morton Heilig's Sensorama Simulator brought 3-D, smells, and feels to the cinema experience in the 1960s.
  71. [71]
    The Sensorama: One of the First Functioning Efforts in Virtual Reality
    In 1962 Heilig built a prototype of his immersive, multi-sensory, mechanical multimodal Offsite Link theater called the Sensorama Offsite Link ...
  72. [72]
    US7934773B2 - Motion-enabled movie theater seat - Google Patents
    The present document describes an actuated chair for inducing motion with respect to the ground as a function of motion signals synchronized with a video ...
  73. [73]
    CJ 4DPLEX Redefines the Cinema Experience - CJ NEWSROOM
    Jun 19, 2025 · With the bold vision of transforming the movie theater into a sensory playground, CJ 4DPLEX was launched in 2009 as a subsidiary of CJ CGV.
  74. [74]
    MediaMation, Inc. Receives U.S. Patent On Shared Drive ... - PRWeb
    Nov 14, 2013 · The patented pneumatic drive mechanism is key to MMI's “master/drone” 4D cinema seats.Missing: algorithms | Show results with:algorithms
  75. [75]
    'Avatar' in 4D at Korean theaters | The Independent
    Feb 20, 2010 · A 4D screening costs $15.80 instead of the average $6.90 ticket price but the 88 seats at the Korean multiplex theater CJ-CGV are selling out.
  76. [76]
    CJ 4DPLEX and Cinépolis Expand Partnership
    Jul 10, 2025 · Since opening its first 4DX theater in Mexico in 2011, Cinépolis has expanded its premium offerings to include 55 4DX theaters, including the ...
  77. [77]
    SimEx-Iwerks creates Ultra-Accessible 4D Magic Cinema ... - Blooloop
    Jun 10, 2025 · SimEx-Iwerks has partnered with Morgan's Wonderland to create the Ultra-Accessible 4D Magic Cinema, featuring a wheelchair motion platform.Missing: 2020s | Show results with:2020s
  78. [78]
    Experimental Study on the Effect of Motion Sickness on 4D Movie ...
    Aug 6, 2025 · It is found that there is a correlation between motion sickness and motion sickness caused by watching 4D movies.
  79. [79]
    Are there side effects to watching 3D movies? A prospective ...
    Seeing 3D movies can increase rating of symptoms of nausea, oculomotor and disorientation, especially in women with susceptible visual-vestibular system.
  80. [80]
    The Time Machine — Ch 1
    There are really four dimensions, three which we call the three planes of Space, and a fourth, Time. There is, however, a tendency to draw an unreal distinction ...
  81. [81]
    The Fourth Dimension - Rudy Rucker
    FLATLAND, first published in 1884, is the story of a square who takes a trip into higher dimensions. A century has passed and people are still talking about it.
  82. [82]
    Sci-fi book where a 3D man travels into 4D world and meets some ...
    Jun 14, 2023 · Spaceland is a science fiction novel by American mathematician and computer scientist Rudy Rucker, and published in 2002 by Tor Books. In a ...
  83. [83]
    The Fourth Dimension in Sound - Wikipedia
    The Fourth Dimension in Sound is an album by bandleader and arranger Shorty Rogers recorded in late 1961 and released on the Warner Bros. label.<|separator|>
  84. [84]
    Four Dimensions - Keith Lay, composer
    Apr 21, 2012 · Four Dimensions is a seven-minute “concert of the future” merging orchestra with music synthesis. An EWI (electronic wind instrument) performs ...
  85. [85]
    Four-Dimensionalism - Theodore Sider - Oxford University Press
    $$59.00 to $210.00 Free delivery 25-day returnsLucid, absorbing, and original, this book defends the theory that the material world is composed of temporal as well as spatial parts.Missing: perdurantism | Show results with:perdurantism
  86. [86]
    [PDF] Four Dimensionalism∗ - Ted Sider
    (2001). Four ...Missing: perdurantism | Show results with:perdurantism
  87. [87]
    Temporal Parts - Stanford Encyclopedia of Philosophy
    Feb 1, 2004 · Perdurantists think that objects have both spatial and temporal parts, while endurantists think that they only have spatial parts. From an ...
  88. [88]
    Persistence in Time | Internet Encyclopedia of Philosophy
    Perdurantism is also known as 'four-dimensionalism'—for perdurantism has it that objects are extended in four dimensions (this contrasts with endurantism, ...
  89. [89]
    Mauro Dorato, Presentism/Eternalism and Endurantism/Perdurantism
    The main claim that I want to defend in this paper is that the there are logical equivalences between eternalism and perdurantism on the one hand and ...
  90. [90]
    What does 4D BIM Mean for Your Construction Business? - TrueCADD
    Feb 18, 2025 · Let's discuss three potential benefits of 4D BIM · Improved planning and management of construction activities · Safer working site · Savings in ...
  91. [91]
    What are 4D and 5D Modeling? | GPRS
    4D modeling is the integration of scheduling data with a 3D BIM model. It helps project teams see the construction sequence. They can find conflicts and improve ...Real-World Applications And... · The Future Of 4d And 5d... · Frequently Asked Questions<|separator|>
  92. [92]
    Optimize Federal Builds: 4D Construction Scheduling Services
    Rating 5.0 (10) Oct 29, 2024 · Achieve timely federal project success! United-BIM's 4D BIM scheduling empowers you to minimize delays, manage risks, and meet your project ...
  93. [93]
    How 4D BIM with AI Supports Commercial Construction Projects?
    Aug 21, 2020 · From collaboration and safety to execution, 4D BIM with AI simplifies construction projects operation, producing cost-effective results.
  94. [94]
    4D Technology - 4D Technology
    4D Technology's Optical Metrology Products assure the quality of precision optics and optical systems. Our Dynamic Interferometry assures the surface and ...Optical Metrology Products · Contact us · About · Careers at 4D Technology
  95. [95]
    Optical Metrology Products - 4D Technology
    4D custom interferometers and laser interferometers overcome difficult environments, complex setups and one-of-a-kind measurement problems.
  96. [96]
    4D Technology Accufiz Interferometers - QD UK
    Flexible, proven and affordable, AccuFiz Fizeau laser interferometers fit well in confined lab spaces and offer high stability in any environment.<|separator|>
  97. [97]
    4D Technology Announces 4D InSpec: The First Handheld, High ...
    4D metrology products utilize state-of-the-art technology that is deployed in production environments, even in the presence of severe vibration and turbulence.
  98. [98]
    Industries - 4D Technology
    4D gauges can be found in industries from aircraft maintenance to furniture production. They measure anywhere in the factory, and anywhere on a component.
  99. [99]
    What are the applications of four-dimensional objects? - Quora
    May 11, 2023 · The geometry of four dimensions is applied (in particular) in Geophysics when computing the volumetric curvatures of geological features.
  100. [100]
    Are there any practical applications for higher dimensional geometry?
    Mar 29, 2016 · But higher dimensional spaces are practical in other ways. One of my favorite examples is parameter space. Suppose you were designing a new cell ...